JP2010065604A - Control device of multi-cylinder engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device for a multi-cylinder engine capable of improving startability of the engine under a cryogenic condition for a multi-cylinder engine using an alcohol mixed fuel.
An ECU 1A, for an engine 50 using an ethanol mixed fuel that is an alcohol mixed fuel, under a very low temperature condition, a fuel injection instruction signal to a first cylinder in a first combustion cycle after the first explosion occurs, An advance angle control means is provided for advancing the fuel injection timing of the first cylinder when the fuel injection instruction signal to the second cylinder different from the one cylinder overlaps. Specifically, the advance angle control means is configured to advance the fuel injection timing when the ethanol concentration of the ethanol mixed fuel is higher than a predetermined value A. Further, the advance angle control means is configured to advance the fuel injection timing to a greater degree as the ethanol concentration is higher, specifically according to the ethanol concentration of the ethanol mixed fuel.
[Selection] Figure 2

Description

  The present invention relates to a control device for a multi-cylinder engine, and more particularly to a control device for a multi-cylinder engine for a multi-cylinder engine using an alcohol mixed fuel.

  Conventionally, FFV (Flexible Fuel Vehicle) equipped with an engine that can use not only gasoline but also alcohol (for example, ethanol) mixed fuel as fuel is known as a vehicle from the viewpoint of fuel resource substitution. In this regard, as a technique considered to be related to the present invention for the multi-cylinder engine equipped with the FFV, for example, techniques related to engine startability are described in Patent Documents 1 to 3.

JP 2007-146826 A JP-A-61-53429 Japanese Patent Laid-Open No. 2002-070618

In FFV, engine startability is poor under extremely low temperature conditions. Here, the cryogenic condition is that in the first combustion cycle after the first explosion that proceeds in each cylinder (especially, the cylinder where fuel injection is performed first after the first explosion occurs) It means that it exists in the temperature range where a large amount of fuel injection is performed so that an injection period overlaps. Specifically, for example, a case where the intake air temperature at the start is within a range of −40 ° C. to −30 ° C. can be set as the cryogenic condition.
In addition, poor engine startability is particularly likely to occur when the alcohol-mixed fuel has a high concentration. In this respect, the engine startability failure occurs specifically for the following reason.

The theoretical air-fuel ratio of ethanol, which is a typical alcohol, is about 9, and the fuel injection amount is about 1.5 times greater than that of gasoline fuel having a theoretical air-fuel ratio of 14.6.
In addition, the evaporability at low temperatures deteriorates particularly when the ethanol-mixed fuel has a high concentration. FIG. 7 is a diagram comparing the fuel distillation characteristics between gasoline fuel and high-concentration ethanol mixed fuel. When the temperature is about 70 ° C. or higher, the high-concentration ethanol mixed fuel has a higher distillation ratio than the gasoline fuel. However, when the temperature is lower than 70 ° C., the high-concentration ethanol mixed fuel has a lower distillation rate than the gasoline fuel. Moreover, the high concentration ethanol mixed fuel shows the tendency for a distillation rate to fall according to the fall of temperature.

Thus, in addition to the fuel injection amount of the ethanol mixed fuel being larger than that of the gasoline fuel, the evaporability at a low temperature is deteriorated particularly when the concentration is high. For this reason, compared with gasoline fuel, the amount of fuel adhering to the wall surface of the intake port at the start of the engine increases, or the amount of fuel evaporation in the cylinder at the start of the engine decreases. For this reason, it is necessary to greatly increase the fuel injection amount at the time of engine start under extremely low temperature conditions (see FIG. 8).
On the other hand, if the fuel injection amount at the time of starting the engine is significantly increased, the fuel injection period may overlap between the cylinders. When the fuel injection period overlaps between the cylinders, the fuel pump simultaneously pumps the fuel to the plurality of cylinders. For this reason, the pumping capacity of the fuel pump necessary for fuel injection will be insufficient, and as a result, the required injection amount that has been greatly increased cannot be injected.
In other words, FFV has a problem that engine startability is poor because the required injection amount cannot be injected as described above under extremely low temperature conditions.

  Therefore, the present invention has been made in view of the above problems, and provides a control device for a multi-cylinder engine that can improve the startability of the engine under cryogenic conditions for a multi-cylinder engine using an alcohol-mixed fuel. The purpose is to do.

  The control apparatus for a multi-cylinder engine according to the present invention for solving the above-described problems is a multi-cylinder engine using an alcohol-mixed fuel, and is applied to the first cylinder in the first combustion cycle after the first explosion under an extremely low temperature condition. Advance angle control means for advancing the fuel injection timing of the first cylinder when a fuel injection instruction signal and a fuel injection instruction signal for a second cylinder different from the first cylinder overlap. It is characterized by.

  Further, the present invention may be configured such that the advance angle control means advances the fuel injection timing to a greater degree as the alcohol concentration is higher in accordance with the alcohol concentration of the alcohol mixed fuel.

  In the present invention, the advance angle control means may advance the fuel injection timing when the alcohol concentration of the alcohol mixed fuel is higher than a predetermined value.

  According to the present invention, the alcohol concentration of the alcohol-mixed fuel is high so that the advance angle control means overlaps the fuel injection instruction signal to the first cylinder and the fuel injection instruction signal to the second cylinder. In some cases, the fuel injection timing may be advanced.

  In addition, the multi-cylinder engine control apparatus of the present invention provides a fuel injection instruction signal to the first cylinder in the first combustion cycle after the first explosion under an extremely low temperature condition for a multi-cylinder engine using an alcohol-mixed fuel, A fuel pressure increase control means for increasing the fuel pressure of the first cylinder when a fuel injection instruction signal to a second cylinder different from the first cylinder overlaps is provided.

  Further, the present invention may be configured such that the fuel pressure increase control means increases the fuel pressure to a greater degree as the alcohol concentration is higher in accordance with the alcohol concentration of the alcohol mixed fuel.

  The fuel pressure increase control means may increase the fuel pressure when the alcohol concentration of the alcohol mixed fuel is higher than a predetermined value.

  Further, according to the present invention, the alcohol concentration of the alcohol-mixed fuel is high so that the fuel pressure increase control means overlaps the fuel injection instruction signal to the first cylinder and the fuel injection instruction signal to the second cylinder. In some cases, the fuel pressure may be increased.

  In addition, the multi-cylinder engine control apparatus of the present invention provides a fuel injection instruction signal to the first cylinder in the first combustion cycle after the first explosion under an extremely low temperature condition for a multi-cylinder engine using an alcohol-mixed fuel, An advance control means for advancing the fuel injection timing of the first cylinder when the fuel injection instruction signal to the second cylinder different from the first cylinder overlaps, When the fuel injection instruction signal to the first cylinder in the first combustion cycle after the explosion occurs and the fuel injection instruction signal to the second cylinder different from the first cylinder overlap, Fuel pressure increase control means for increasing the fuel pressure is provided.

  Further, the present invention may be configured to further include a correction control means for calculating a correction amount of the fuel pressure when the first explosion that has occurred does not complete.

  ADVANTAGE OF THE INVENTION According to this invention, the startability of an engine on cryogenic conditions can be improved about the multicylinder engine which uses alcohol mixed fuel.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 schematically shows a control device for a multi-cylinder engine according to the present embodiment realized by an electronic control unit (ECU) 1A together with related components such as an engine 50 which is a multi-cylinder (here, four-cylinder) engine. FIG. The fuel supply system 10 includes a fuel tank 11, a fuel pump 12, a fuel filter 13, and a pressure regulator 14. The fuel tank 11 stores an ethanol mixed fuel that is a mixed fuel of ethanol and gasoline. The fuel tank 11 is provided with an alcohol sensor 20 for detecting the ethanol concentration of the ethanol mixed fuel. Specifically, for example, a sensor that detects the electric conductivity of the fuel that changes according to the alcohol concentration can be applied to the alcohol sensor 20. The fuel pump 12 supplies the ethanol mixed fuel in the fuel tank 11 to the injector 51 through the fuel filter 13. At this time, surplus fuel is returned to the fuel tank 11 by the action of the pressure regulator 14. The fuel supply system 10 is configured as a variable fuel pressure system that can linearly control the fuel pressure to the required fuel pressure.

The engine 50 is provided with an injector 51 for each cylinder. Specifically, the injector 51 is arranged to inject fuel into the intake port 55. The engine 50 is provided with a spark plug 52 for each cylinder. An ignition voltage distributed by the distributor 53 is applied to the spark plug 52. The distributor 53 distributes the high voltage output from the igniter 54 to each spark plug 52 in synchronization with the crank angle of the engine 50. The ignition timing of each spark plug 52 is determined by the high voltage output timing from the igniter 54.
The engine 50 is provided with a water temperature sensor 71 for detecting the cooling water temperature, a crank angle sensor 72 used for detecting the rotational speed NE, and the like.

  The ECU 1A includes a microcomputer including a CPU, a ROM, a RAM, and the like (not shown), an input / output circuit, and the like. The ECU 1A is mainly configured to control the engine 50. In this embodiment, specifically, the ECU 1A is configured to control the injector 51, the igniter 54, and the like. These objects to be controlled are electrically connected to the ECU 1A. Various sensors such as a water temperature sensor 71, a crank angle sensor 72, and an intake air temperature sensor 73 for detecting intake air temperature are electrically connected to the ECU 1A. The ROM is configured to store a program describing various processes executed by the CPU, map data, and the like. The ECU 1A executes various processes based on a program stored in the ROM while using a temporary storage area of the RAM as necessary, so that various control means, determination means, detection means, calculation means, and the like are functional in the ECU 1A. To be realized. In this regard, in the ECU 1A, in particular, the following advance angle control means and fuel pressure increase control means are functionally realized.

The advance angle control means includes a fuel injection instruction signal to the first cylinder and a fuel injection instruction signal to a second cylinder different from the first cylinder in the first combustion cycle after the first explosion under a cryogenic condition. If they overlap, the fuel injection timing of the first cylinder is advanced.
In this regard, the advance angle control means specifically determines that the alcohol concentration is the predetermined value A when the alcohol concentration of the alcohol-mixed fuel (specifically, the ethanol concentration, and so on) is higher than the predetermined value A. The fuel injection timing is advanced from the following case. The predetermined value A is set in advance to correspond to the case where the alcohol concentration of the alcohol-mixed fuel is high enough that the fuel injection instruction signal to the first cylinder and the fuel injection instruction signal to the second cylinder overlap. . The predetermined value A can be a constant value (for example, 85%), but is not limited to this, and may be a variable value set in advance so that the magnitude thereof changes according to the intake air temperature, for example. .
Specifically, the advance angle control means advances the fuel injection timing at least in the first combustion cycle after the occurrence of the first explosion at least for the cylinder in which the fuel injection is performed first after the occurrence of the first explosion. This is because, as a result of the rapid increase in the rotational speed NE due to the first explosion, the overlap of the fuel injection period with other cylinders in the first combustion cycle after the first explosion occurs, particularly for the cylinder where fuel injection is performed first. This is because it becomes easy to occur.
Further, when the fuel injection timing is advanced, the advance control means specifically advances the fuel injection timing to a greater degree as the alcohol concentration of the alcohol-mixed fuel is higher. In this regard, specifically, the fuel injection timing is advanced by the required advance amount ΔAinj. The required advance amount ΔAinj is obtained by determining the magnitude of the predetermined value C as described later, and setting the determined predetermined value C as the required advance amount ΔAinj.

The fuel pressure increase control means determines whether the fuel injection instruction signal to the first cylinder in the first combustion cycle after the first explosion occurs and the fuel injection instruction signal to the second cylinder different from the first cylinder overlap. Increase the fuel pressure of one cylinder.
Specifically, the fuel pressure increase control means increases the fuel pressure when the alcohol concentration of the alcohol-mixed fuel is higher than the predetermined value A than when the alcohol concentration is equal to or lower than the predetermined value A.
Specifically, the fuel pressure increase control means increases the fuel pressure at least in the first combustion cycle after the occurrence of the first explosion at least for the cylinder in which fuel injection is performed first after the occurrence of the first explosion.
In further increasing the fuel pressure, specifically, the fuel pressure increase control means increases the fuel pressure to a greater degree as the alcohol concentration of the alcohol-mixed fuel increases. In this respect, specifically, the fuel pressure is increased by an amount corresponding to the increase in fuel pressure requirement. The fuel pressure request increase amount is obtained by determining the magnitude of the predetermined value D as described later, and setting the determined predetermined value D as the fuel pressure request increase amount.

Next, the operation of the ECU 1A will be described with reference to FIGS. FIG. 2 is a diagram showing the operation of the ECU 1A in a flowchart, and FIG. 3 is a diagram showing an example of a time chart corresponding thereto. In the ECU 1A, the process shown in the flowchart of FIG. 2 is repeatedly executed at very short time intervals. In FIG. 3, the state of a conventional fuel injection instruction signal that does not change the fuel injection timing and the fuel pressure is also shown for reference.
First, FIG. 3 will be described. When cranking is started as shown in FIG. 3, the rotational speed NE increases accordingly. The strokes of the combustion cycles of the cylinders # 1 to # 4 at the start of cranking are a compression stroke, an intake stroke, an exhaust stroke, and an expansion stroke, respectively. In this state, ignition is performed in the # 1 cylinder in the compression stroke, and a fuel injection instruction is issued to the # 3 cylinder in the intake stroke. The fuel pressure is set to a size necessary for injecting the required injection amount in each cylinder.

  Subsequently, in the state of proceeding to the next stroke, since the first explosion did not occur in the # 1 cylinder, the magnitude of the rotational speed NE remains unchanged. At this time, ignition is performed in the # 3 cylinder in the compression stroke, and a fuel injection instruction is issued to the # 4 cylinder in the intake stroke. In this example, the first explosion occurs in the # 3 cylinder that has been ignited, and the rotational speed NE increases accordingly. On the other hand, in the state of proceeding to the next stroke, ignition is performed in the # 4 cylinder in the compression stroke, and a fuel injection instruction is issued to the # 2 cylinder in the intake stroke. That is, in this example, the # 2 cylinder is a cylinder in which the first fuel injection is performed after the first explosion occurs, and the # 2 cylinder is a cylinder corresponding to the first cylinder. In addition, after the first explosion, the first combustion cycle is from the intake stroke where fuel injection is performed to the next exhaust stroke (not shown) for the # 2 cylinder.

  However, when the rotational speed NE suddenly increases due to the first explosion, for example, for # 2 cylinder, the time from the intake stroke to the next compression stroke is shortened, but even in this case, it is greatly increased. It is necessary to inject the required injection amount. Therefore, in the conventional example, the fuel injection instruction given to the # 2 cylinder to inject the required injection amount is performed from the intake stroke to the next compression stroke. For this reason, in the conventional example, the fuel injection instruction signals for the # 1 cylinder and the # 2 cylinder are overlapped in the state of proceeding to the next stroke. In this example, the # 1 cylinder is a cylinder corresponding to the second cylinder.

  With respect to such a starting mode of the engine 50, the ECU 1A performs processing as shown in FIG. First, the ECU 1A determines whether or not there is an engine (E / G) start request (step S11). Whether or not there is an engine start request can be determined, for example, by whether or not the ignition SW is ON. If the determination is affirmative, the ECU 1A estimates the intake air temperature and the ethanol concentration based on the sensor output (step S12). That is, the fuel property is determined in this step. The alcohol concentration may be appropriately detected (estimated) using a known technique, for example. In this regard, the alcohol concentration may be detected based on the output of an A / F sensor for detecting the exhaust air-fuel ratio of the engine 50, for example. Subsequently, the ECU 1A determines whether or not the estimated ethanol concentration is greater than a predetermined value A (step S13). In this step, it is determined whether or not the fuel is a high-concentration ethanol mixed fuel. In this regard, when the ethanol concentration is larger than the predetermined value A, in the conventional example, as shown in FIG. 3, the fuel injection instruction signal to the # 2 cylinder corresponding to the first cylinder and the # corresponding to the second cylinder are displayed. The fuel injection instruction signal for one cylinder overlaps.

  If a positive determination is made in step S13, it is determined that the fuel is high-concentration ethanol fuel. At this time, the ECU 1A determines whether or not the estimated intake air temperature is smaller than a predetermined value B (step S14). The predetermined value B is a value set in advance to determine whether or not it is a cryogenic condition, and can be set to −30 ° C., for example. In this step, it is determined whether or not the cryogenic condition is satisfied. If a negative determination is made in step S11, S13, or S14, no special process is required, and thus this flowchart is temporarily terminated.

  On the other hand, if an affirmative determination is made in step S14, it is determined that the cryogenic condition is satisfied. At this time, the ECU 1A acquires information on the initial explosion determination flag that is set to ON when the initial explosion occurs (step S15), and determines whether or not the initial explosion determination flag is ON (step S16). Whether or not the first explosion has occurred can be determined by, for example, whether or not the rotational speed NE has increased. If a negative determination is made in step S16, the process returns to step S15.

  On the other hand, if the determination in step S16 is affirmative, the ECU 1A sets the required advance angle amount ΔAinj of the injection timing to a predetermined value C (step S17). The predetermined value C is preset in the map data so as to increase as the ethanol concentration increases in accordance with the ethanol concentration as schematically shown in FIG. For this reason, as the ethanol concentration increases, the fuel injection timing can be advanced to a greater degree. Subsequently, the ECU 1A sets the fuel pressure request increase amount to a predetermined value D (step S18). As shown schematically in FIG. 5, the predetermined value D is set in advance in the map data so as to increase as the ethanol concentration increases in accordance with the ethanol concentration. For this reason, the fuel pressure can be increased to a greater degree as the ethanol concentration is higher. Note that the map data shown in FIGS. 3 and 4 is stored in the ROM in advance.

In step S17 described above, the fuel injection timing of the # 2 cylinder where fuel injection is first performed after the initial explosion occurs is advanced by the required advance amount ΔAinj. Further, in step S18 described above, the fuel pressure increases, so the fuel injection period of the # 2 cylinder is shortened. Therefore, according to the ECU 1A, it is possible to avoid the overlapping of the fuel injection instruction signals for the # 1 cylinder and the # 2 cylinder as shown in FIG. As a result, the pumping capacity of the fuel pump 12 necessary for fuel injection is insufficient, and as a result, it is possible to avoid that the required injection amount greatly increased cannot be injected, thereby improving the startability of the engine 50. it can. Moreover, since the atomization of the fuel is promoted by the increase of the fuel pressure, the combustion can be promoted, thereby reducing the unburned HC discharged at the start.
As described above, the ECU 1A can improve the startability of the engine 50 under the cryogenic condition even when the high-concentration ethanol fuel is used for the engine 50 using the ethanol mixed fuel. The ECU 1A can also reduce unburned HC discharged at the time of starting.

  The ECU 1B according to the present embodiment is substantially the same as the ECU 1A except that the ECU 1B further includes the following correction control means. Each configuration related to the ECU 1B is the same as that of the ECU 1A. For this reason, in this embodiment, the ECU 1B and related components are not shown. The correction control means can be realized by changing a program stored in the ROM of the ECU 1A.

The correction control means calculates the correction amount of the fuel pressure when the first explosion that has occurred does not complete.
Specifically, the correction control means calculates the fuel pressure correction amount based on the engine starting state or combustion state. That is, according to the torque of the engine 50 when the first explosion is not completed, the correction amount of the fuel pressure is calculated so that the fuel pressure is increased more as the torque generated by the first explosion is smaller.
Further, in calculating the fuel pressure correction amount in this way, the correction control means more specifically calculates the fuel pressure correction amount based on the output (or rotational speed NE) of the crank angle sensor 72. However, the present invention is not limited to this, and the correction control means can calculate the correction amount of the fuel pressure based on the in-cylinder pressure, for example.
In the present embodiment, whether or not the first explosion has been completed is determined based on whether or not the rotational speed NE has decreased, as will be described later, but whether or not the first explosion has been completed is not limited to this. The determination may be made as appropriate based on the 50 starting states or combustion states. In this regard, whether or not the first explosion has been completed can be determined based on, for example, the in-cylinder pressure.

  Next, the operation of the ECU 1B will be described using the flowchart shown in FIG. This flowchart is the same as the flowchart shown in FIG. 2 except that steps S21 to S25 are added. Therefore, in the present embodiment, these steps will be particularly described. Subsequent to step S18, the ECU 1B determines whether or not the rotational speed NE has decreased (step S21). If the determination is affirmative, the ECU 1B turns on a rotation speed NE decrease flag indicating that the rotation speed NE has decreased (step S22). If the determination is negative, the ECU 1B turns off the rotation speed NE decrease flag (step S23). . Subsequently, the ECU 1B determines whether or not the rotation speed NE decrease flag is ON (step S24). If the determination is negative, it is determined that the explosion has been completed because the rotational speed NE has increased. Since no special processing is required at this time, this flowchart is terminated.

On the other hand, if the determination in step S24 is affirmative, it is determined that the complete explosion has not occurred because the rotational speed NE has decreased. Such a situation may occur, for example, when the performance of the injector 51 or the spark plug 52 is deteriorated due to a change with time. Therefore, if the determination in step S24 is affirmative, the ECU 1B corrects the fuel pressure (step S25). Specifically, as described above, the correction amount is calculated so that the fuel pressure is increased as the torque generated by the first explosion is smaller, and the fuel pressure is corrected by the calculated correction amount. As a result, atomization of the fuel can be promoted. Therefore, even if the start-up failure of the engine 50 occurs due to the change over time or the like, the start-up performance of the engine 50 is reduced. Can be improved. If the first explosion is not completed, the next routine is executed with the next explosion as the first explosion.
In this way, the ECU 1B improves the startability of the engine 50 by further promoting atomization of the fuel even if the start failure of the engine 50 occurs without completing the initial explosion as compared with the ECU 1A. be able to.

The embodiment described above is a preferred embodiment of the present invention. However, the present invention is not limited to this, and various modifications can be made without departing from the scope of the present invention.
For example, the advance angle control means may advance the fuel injection timing as the intake air temperature is lower in place of the alcohol concentration of the alcohol-mixed fuel or in accordance with not only the alcohol concentration but also the intake air temperature. Further, the fuel pressure raising means may raise the fuel pressure as the intake air temperature is lower, instead of the alcohol concentration of the alcohol mixed fuel, or according to not only the alcohol concentration but also the intake air temperature. In this respect, it is possible to avoid the overlap of the fuel injection timing with high accuracy by advancing the fuel injection timing or increasing the fuel pressure according to the alcohol concentration and the intake air temperature.

  Further, for example, the advance of the fuel injection timing related to the advance angle control means and the increase of the fuel pressure related to the fuel pressure increase control means are necessary to prevent the fuel injection timing from overlapping between cylinders as necessary. It may be appropriately performed in the cylinder, and may be continued as necessary for a necessary period. At this time, the advance angle of the fuel injection timing and the increase degree of the fuel pressure may be appropriately changed.

  The advance angle control means, the fuel pressure increase control means, and the correction control means are rationally realized by the ECU 1, but are realized by hardware such as other electronic control devices, dedicated electronic circuits, or a combination thereof. Also good. In this regard, the engine control device of the present invention may be realized by, for example, a plurality of electronic control devices or a combination of electronic control devices and hardware such as electronic circuits. That is, the engine control apparatus of the present invention may be realized in a distributed control manner, for example. Similarly, each means such as the advance angle control means may be realized in a distributed control manner.

It is a figure which shows ECU1A typically with each structure concerned. It is a figure which shows operation | movement of ECU1A with a flowchart. It is a figure which shows an example of the time chart corresponding to the flowchart shown in FIG. It is a figure which shows the map data of the predetermined value 3 typically. It is a figure which shows the map data of the predetermined value 4 typically. It is a figure which shows operation | movement of ECU1B with a flowchart. It is a figure which compares the distillation characteristic of a fuel with the case of a gasoline fuel, and the case of a high concentration ethanol mixed fuel. It is a figure which compares the mode of the request | requirement injection quantity at the time of starting of the ethanol mixed fuel according to ethanol concentration with the case where it is normal temperature, and the case where it is very low temperature. For reference, the case where the fuel is gasoline fuel is also shown.

Explanation of symbols

1 ECU
10 Fuel supply system 10
DESCRIPTION OF SYMBOLS 11 Fuel tank 12 Fuel pump 13 Fuel filter 14 Pressure regulator 20 Alcohol sensor 50 Engine 51 Injector 52 Spark plug 53 Distributor 54 Igniter 55 Intake port 71 Water temperature sensor 72 Crank angle sensor 73 Intake temperature sensor

Claims (10)

For multi-cylinder engines that use alcohol blended fuel,
When the fuel injection instruction signal to the first cylinder in the first combustion cycle after the first explosion occurs overlaps with the fuel injection instruction signal to the second cylinder different from the first cylinder under a cryogenic condition. A control apparatus for a multi-cylinder engine, comprising an advance angle control means for advancing the fuel injection timing of the first cylinder. 2. The multi-cylinder engine according to claim 1, wherein the advance angle control means advances the fuel injection timing to a greater degree as the alcohol concentration is higher in accordance with the alcohol concentration of the alcohol mixed fuel. Control device. 3. The control apparatus for a multi-cylinder engine according to claim 1, wherein the advance angle control means advances the fuel injection timing when the alcohol concentration of the alcohol mixed fuel is higher than a predetermined value. When the alcohol concentration of the alcohol-mixed fuel is high such that the advance angle control means overlaps the fuel injection instruction signal to the first cylinder and the fuel injection instruction signal to the second cylinder, 4. The control apparatus for a multi-cylinder engine according to claim 3, wherein the injection timing is advanced. For multi-cylinder engines that use alcohol blended fuel,
When the fuel injection instruction signal to the first cylinder in the first combustion cycle after the first explosion occurs overlaps with the fuel injection instruction signal to the second cylinder different from the first cylinder under a cryogenic condition. A control apparatus for a multi-cylinder engine, comprising fuel pressure increase control means for increasing the fuel pressure of the first cylinder. 6. The engine control device according to claim 5, wherein the fuel pressure increase control means increases the fuel pressure to a greater degree as the alcohol concentration is higher in accordance with the alcohol concentration of the alcohol mixed fuel. The engine control device according to claim 5 or 6, wherein the fuel pressure increase control means increases the fuel pressure when the alcohol concentration of the alcohol mixed fuel is higher than a predetermined value. When the alcohol concentration of the alcohol-mixed fuel is high such that the fuel pressure increase control means overlaps the fuel injection instruction signal to the first cylinder and the fuel injection instruction signal to the second cylinder. The controller for a multi-cylinder engine according to claim 7, wherein For multi-cylinder engines that use alcohol blended fuel,
When the fuel injection instruction signal to the first cylinder in the first combustion cycle after the first explosion occurs overlaps with the fuel injection instruction signal to the second cylinder different from the first cylinder under a cryogenic condition. An advance angle control means for advancing the fuel injection timing of the first cylinder;
When the fuel injection instruction signal to the first cylinder in the first combustion cycle after the first explosion occurs overlaps with the fuel injection instruction signal to the second cylinder different from the first cylinder under a cryogenic condition. And a fuel pressure increase control means for increasing the fuel pressure of the first cylinder. The control apparatus for a multi-cylinder engine according to any one of claims 1 to 9, further comprising correction control means for calculating a correction amount of the fuel pressure when the generated first explosion is not completed.

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