KR20050022323A - Starting control method of a car for reducing HC and harmful gas emissions - Google Patents

Abstract

PURPOSE: A starting control method of a vehicle for reducing discharge of harmful exhaust gas including noncombustible hydrocarbon is provided to prevent incomplete combustion by skipping fuel injection to cylinders during the engine cycle and preheating the cylinder with the compression heat of the piston. CONSTITUTION: An ECU(Electronic Control Unit) detects the starting or restarting state of an engine(S-0), and sets sensors including encoders, amplifiers including converters and a data acquisition system to be operated(S-1). The fuel injection time of a first cylinder is decided by calculating data from the data acquisition system with the ECU, and switches connected to a fuel injection valve and an ignition plug are turned off to restrict fuel injection to the first cylinder and combustion of fuel(S-2). The ECU decides the fuel injection time of a third cylinder by calculating data from the data acquisition system, and turns on the switches connected to the fuel injection valve and the ignition plug to inject fuel into the third cylinder and to burn fuel(S-3). The fuel injection time of a fourth cylinder is decided by calculating data from the data acquisition system with the ECU, and the switches are turned off to restrict fuel injection to the fourth cylinder and combustion of fuel(S-4). The ECU decides the fuel injection time of a second cylinder by calculating data from the data acquisition system, and turns on the switches connected to the fuel injection valve and the ignition plug to inject fuel into the second cylinder and to burn fuel(S-5).

Description

Starting control method of a car for reducing HC and harmful gas emissions

The present invention relates to a vehicle start control method for reducing emissions of harmful gases including unburned hydrocarbons, and more particularly, one to three engine cycles are operated from an engine start when the vehicle is started or restarted after an idle stop. During the process, fuel injection is skipped into each cylinder, and the internal temperature of the cylinder where no fuel is injected is preheated by the heat of compression by the piston, and thus the internal temperature of the cylinder is heated to a predetermined temperature. By injecting normal fuel into each cylinder, it is possible to reduce the emission of harmful gases including unburned hydrocarbons caused by incomplete combustion of fuel during initial engine start or idle stop start. The method of controlling the starting of the car for reducing the emission of gas .

In general, a gasoline engine used in a car is a spark ignition type that compresses a gasoline and air mixer in a cylinder, ignites and combusts an electric flame-compressed mixer to reciprocate the piston with the explosive force generated by the combustion of the mixer. It is a reciprocating internal combustion engine, and in the case of diesel engines, the air is compressed at a volume ratio of about 20 times inside the cylinder to raise the temperature of the combustion chamber to about 500 to 700 ° C, which is worse than gasoline and easily vaporized in a carburetor. It is a compression ignition type reciprocating internal combustion engine in which no petroleum fuel such as kerosene, light oil or heavy oil is injected into this high temperature and high pressure air to spontaneously ignite and burn the fuel.

Gasoline engines and diesel engines used in automobiles are somewhat different in the ignition method as described above, but inject the mixer or petroleum fuel at an appropriate ratio according to the output required inside each cylinder consisting of four or six cylinders. This allows the fuel to be sequentially burned in the combustion chamber of each cylinder, and has an almost similar structure in that it is an internal combustion engine capable of obtaining power by rotating the crankshaft connected to the piston with the explosive force generated by the combustion of such fuel. Therefore, each engine has to smoothly burn fuel inside the cylinder to increase the output of the vehicle and the performance of the engine, and to reduce the amount of harmful emissions emitted from the vehicle.

As described above, the combustion of fuel generated from the cylinder of the automobile engine is performed relatively smoothly while the cylinder is sufficiently heated as in the driving of the automobile, but the inner wall of the cylinder and the engine such as the cold starting of the vehicle are In the state where the temperature of each component is lowered, the combustion of fuel cannot be performed smoothly inside the cylinder, which is relatively less related to the fuel mixing ratio of the exhaust gas and incomplete combustion due to the lower temperature of the combustion chamber (misfire, Misfire). There is a problem that the emissions of harmful gases, including unburned hydrocarbons (HC) are greatly affected at the start of the vehicle.

In particular, a recent engine has a large amount of fuel present in the liquid state at the port side so that fuel can be injected rapidly and continuously toward the rear of the valve when the intake valve is closed for the purpose of improving its startability. When the liquid fuel flowing into the cylinder does not vaporize rapidly due to the inner wall temperature of the lower cylinder and most of the fuel collides with the piston head near the compression top dead center, it not only adversely affects the startability of the vehicle, but also the cold cylinder. Some of the fuel condensed on the inner wall has a problem of greatly increasing the emission of unburned hydrocarbons (HC) by incomplete combustion by starting vaporization after the fuel is ignited (gasoline engine) and ignition (diesel engine). If part of the condensation occurs on the cold cylinder inner wall The problem is that the emissions of harmful gases including unburned hydrocarbons (HC) are raised to serious levels.

In addition, due to the rapid spread of automobiles in recent years, not only the time of commencement and commute, but also traffic jams occur almost all the time. By stopping the car frequently, most fuel-efficient cars are equipped with an idle-stop system that automatically stops the engine 3 to 5 seconds after stopping the car to prevent unnecessary fuel waste. Therefore, the higher the fuel-efficient cars installed with such a system, the more cold-started the engine is if the engine is restarted without heating enough, resulting in more air pollution by the release of harmful gases including unburned hydrocarbons. There was a problem that caused .

The present invention has been made to solve the conventional problems as described above, the vehicle start control method for reducing the emissions of harmful gases including unburned hydrocarbons according to the present invention is the engine upon restarting the vehicle after the initial start or idle stop Fuel injection is skipped into each cylinder during the operation of one to three engine cycles from the start of the engine, and the internal temperature of the cylinder where no fuel is injected is preheated by the heat of compression by the piston. By heating the internal temperature of the cylinder to a certain temperature and then normal fuel injection into each cylinder, the harmful gases including unburned hydrocarbons generated by incomplete combustion of fuel at the initial startup of the engine or restarting after the idle stop It is the technical problem to make it possible to reduce emissions.

In order to achieve the above object, the present invention has a plurality of cylinders, the several cylinders are ignited in a predetermined ignition order in the start control method of the engine to achieve a normal cycle, (a) the engine starting or restarting state Determining; And (b) repeating at least one or more fuel skip cycles in which ignition and skip are alternately performed according to the ignition order of the cylinder when the starting or restarting state is performed in step a. to be.

The skip is characterized in that consisting of stopping the fuel supply to the cylinder.

The above ignition sequence is characterized by starting with either ignition or skip.

The fuel skip cycle is preferably repeated one to three times.

Hereinafter, the present invention will be described in detail.

The key point of the present invention is that when the engine is started in the stopped state or restarted after the engine stops automatically in the idle stop system, the fuel is not injected by alternating the ignition and skip according to the ignition order of the cylinder. If the fuel is injected by raising the temperature of the combustion chamber wall, it will induce complete combustion.

Accordingly, the engine may be sufficiently heated through the preheating, thereby excluding the cold start state, thereby reducing the emission of harmful gases including unburned hydrocarbons (HC) due to incomplete combustion.

The present invention is divided into a start / restart determination step and a fuel skip cycle step.

Whether to start or restart may be determined through operation information of a fuel injection valve for injecting fuel into the cylinder or an ignition plug for burning fuel in the cylinder.

If the engine is in the state of starting or restarting in the above judgment, the process proceeds to a fuel skip cycle for heating the engine.

The engines of a general automobile are largely a series engine, a V engine, and an oppoed engine. The above classification is based on the arrangement of the engine cylinders, in series engines, all cylinders are arranged in a straight line along the crankshaft, V engines are divided into two sets and arranged along the crankshaft in the form of V mutually, The opposite engine is 180 degrees with the angle between the cylinders wider than that of the V engine.

1 to 3 are conceptual diagrams of a serial engine, a V engine, and an opposing engine, and show cylinder numbers of an engine.

The cylinder number of the serial engine is determined in ascending order from the far side from the output side with respect to the output side of the engine when the engine is viewed from above.

The cylinder number of the V engine is determined in ascending order from the left side to the far side from the output side when the engine is viewed directly from above, and from the far side from the output side of the next right side to the ascending order after the end number of the left side group. All.

The cylinder number of the opposite engine is determined in the same way as the V engine.

The fuel skip cycle phase consists of alternating ignition and skip in the unique ignition sequence of the engine in the normal cycle.

For example, if the ignition sequence of a six-cylinder in-line engine is 1-5-3-6-2-4, the ignition of the fuel skip cycle will be 1-S-3-S-2-S or S-5-S-6. In the order of -S-4. 'S' in the above means a fuel injection skip does not inject fuel.

That is, since the skip should be made alternately with the ignition, it is sufficient to select either skip or ignition in the first cylinder, and arrange the skip and ignition alternately according to the ignition order.

In addition, it is preferable to perform the fuel skip cycle at least once or more and once to three times for sufficient heating of the engine.

The skip consists of supplying no fuel to the cylinder. Therefore, in the cylinder in which the skip is performed, the piston sucks, compresses, expands, and exhausts air by the force supplied from the cylinder in which the ignition is performed, or increases the temperature of the combustion chamber wall surface.

As described above, after the end of the fuel skip cycle several times, normal combustion is performed according to the unique ignition sequence of each engine.

Table 1 summarizes the ignition sequence of the normal cycle according to the engine type and the ignition sequence of the fuel skip cycle according to the ignition sequence.

The ignition sequence of the fuel skip cycle can be determined in the same manner for the engines other than those described in Table 1.

Engine type Number of cylinders Normal cycle ignition sequence Fuel Skip Cycle Ignition Sequence Serial Engine 3 1-3-2 1-S-21-3-SS-3-2 4 1-3-4-2 1-S-4-S S-3-S-2 1-2-4-3 1-S-4-S S-2-S-3 5 1-2-4-5-3 1-S-4-S-5 S-2-S-4-S-3 6 1-5-3-6-2-4 1-S-3-S-2-SS-5-S-6-S-4 1-2-4-6-5-3 1-S-4-S-5-SS-2-S-6-S-3 1-4-2-6-3-5 1-S-2-S-3-SS-4-S-6-S-5 1-4-5-6-3-2 1-S-5-S-3-SS-4-S-6-S-2 8 1-6-2-5-8-3-7-4 1-S-2-S-8-S-7-SS-6-S-5-S-3-S-4 1-3-6-8-4-2-7-5 1-S-6-S-4-S-7-SS-3-S-8-S-2-S-5 1-4-7-3-8-5-2-6 1-S-7-S-8-S-2-SS-4-S-3-S-5-S-6 1-3-2-5-8-6-7-4 1-S-2-S-8-S-7-SS-3-S-5-S-6-S-4 V engine 4 1-3-2-4 1-S-2-SS-3-S-4 6 1-2-5-6-4-3 1-S-5-S-4-SS-2-S-6-S-3 1-4-5-6-2-3 1-S-5-S-2-SS-4-S-6-S-3 8 1-6-3-5-4-7-2-8 1-S-3-S-4-S-2-SS-6-S-5-S-7-S-8 1-5-4-8-6-3-7-2 1-S-4-S-6-S-7-SS-5-S-8-S-3-S-2 1-8-3-6-4-5-2-7 1-S-3-S-4-S-2-SS-8-S-6-S-5-S-7 Opposed engine 4 1-4-3-2 1-S-3-SS-4-S-2

※ 'S' in the table means skip.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Example used a four-cylinder in-line engine.

Figure 4 is a schematic diagram showing an experimental apparatus applied to the control method of the present invention, Figure 5 is a flow chart showing a control method of the present invention, Figures 6 to 9 is the result of applying the fuel skip cycle under each cooling water temperature conditions 10 is a graph showing the emission reduction effect of unburned hydrocarbons according to the control method of the present invention.

First, the experimental apparatus used for the present invention, as shown in Figure 4, the dynamometer and the drive to enable the operation of the engine 10 itself in order to analyze the restart characteristics by the initial start and idle stop of the four-cylinder gasoline engine Of the fuel injection valve 14 and the cylinder 11 for injecting fuel from the fuel tank 12 to the interior of each cylinder 11 through the fuel supply pipe 13 with the connecting shaft of The operation of the spark plug 15 for burning fuel was controlled by an ECU 21 (Electronic Control Unit) connected to the switches 17 and 18, and the gasoline engine used in this experiment was used. The main points of are shown in Table 2.

subject Detail Engin type IL 4, DOHC Bore X Stroke (mm) (cylinder volume) 76.5 × 81.5 Compression ratio 9.5 Displacement Volume (cc) 1,498 Max. Power (PS / rpm) (maximum power) 100 / 6,000 Max. Torque (kgfm / rpm) (maximum output) 14.0 / 3,000 Valve Timing IVO (BTDC) / IVC (ABDC) EVO (BBDC) / EVC (ATDC) 8 CA / 42 CA 42 CA / 8 CA Starter (kW) 0.8

In addition, an encoder 20 (Encoder; Koyo Co., 360ppr) is installed on the camshaft 19 for the operation of the intake and exhaust valves so that the fuel injection timing to each cylinder 11 can be detected. Each pulse, that is, one pulse is generated from the encoder 20 every 1 degree of rotation angle of the camshaft 19, and the pulse generated as described above is passed through the frequency-to-voltage converter 26 (FV Converter). The fuel injection valve 14 and the ignition plug 15 are detected by detecting the fuel injection timing of each cylinder 11 in the ECU 21 according to the input data by being inputted to the collection device 29 (Data acquisition system). It is possible to selectively control the operation of.

In addition, in order to ensure consistency in the experimental conditions according to the start control method of the present invention, all the experiments were made at the suction top dead center of the fourth cylinder (11d) of the engine 10, the pressure in the cylinder 11 is fourth Data values measured from a piezoelectric pressure sensor 23 (Piezoresistive pressure sensor; Kistler, 6052 & 6517A) in the form of a spark plug installed in the cylinder 11d are passed through an amplifier 25 and a data collection device 29 It is possible to measure the pressure by inputting), and the ignition timing, fuel injection timing and air-fuel ratio of the engine 10 are not arbitrarily adjusted, and the temperature of the coolant is controlled at the initial start of the vehicle, that is, during cold start or idle stop. In order to meet the same situation as when restarting by using a cooling water temperature controller (not shown) was adjusted to 30 ℃, 50 ℃, 70 ℃ and 90 ℃.

The unburned hydrocarbons discharged to the exhaust manifold 16 when the engine 10 is started and restarted are FRFIDs capable of measuring the concentration of unburned hydrocarbons in the exhaust manifold 16 connected to the fourth cylinder 11d in real time. Measured by inserting a sampling probe 24 (FID probe) of the Fast Response Flame Ionization Detecter, and the distance from the exhaust valve stem to the tip of the probe rod 24 to minimize the measurement delay on the emission characteristics of unburned hydrocarbons. In order to analyze the characteristics of unburned hydrocarbons in the fourth cylinder (11d), an experiment was carried out by mounting a sampling probe rod in the form of a spark plug in the cylinder (11d), and the exhaust manifold (16) At the rear end, the UEGO (Universal Exhaust Gas Oxygen) sensor was installed as the air-fuel ratio sensor 22 for measuring the air-fuel ratio of the exhaust gas, and the signals input from the reading rods 24 and the sensors 22 Via the amplifier 27 (28) to be input to the data acquisition device 29.

Fig. 5 shows a flowchart for carrying out the method for controlling the starting of a vehicle according to the present invention, which is programmed in the ECU 21 of the experimental apparatus. This is because when the engine starts in the initial start of the vehicle, i.e. during the cold start or during the driving of the car, the engine 10 is restarted after the idle stop is restarted. After the step (S-0) of identifying the starting and restarting state of the (10), each of the sensors 22, 23, 24 including the encoder (20) and the amplifier (26) including a corresponding transducer (26) 25, 27, 28 and the setting step (S-1) for setting the data collection device 29 in an operable state.

As described above, the starter motor (not shown) is operated so that the crankshaft can be rotated by a predetermined speed or more in the stopped state of the engine 10 at the same time as the setting step S-1 by the ECU 21. This rotation is started, which causes the crankshaft and the camshaft 19 of the intake and exhaust valves connected to the timing belt or the timing gear to rotate together with the crankshaft, whereby the fourth cylinder 11d at the first suction top dead center position. Of the first and third cylinders starting with the lowering of the piston of the first cylinder 11a, the explosive stroke of the first cylinder 11a, the exhaust stroke of the second cylinder 11b, and the compression stroke of the third cylinder 11c. In the order of the fourth and second cylinders, the general engine cycle, which is to explode, is operated.

According to an embodiment of the present invention, the fuel injection is skipped into each cylinder 11 during the operation of the general engine cycle as described above, and thus the combustion chamber temperature of the cylinder 11 in which fuel is not injected is changed by the piston. It is possible to raise in advance by the heat of compression of air, thereby minimizing the effect of the cooling zone on the wall of the combustion chamber of the cylinder 11 on the mixer or petroleum fuel. It is designed to reduce the emission of harmful gases including unburned hydrocarbons due to incomplete combustion of fuel at restart.

For this purpose, after the setting step (S-1), the pulse generated from the encoder 20 in accordance with the rotation of the cam shaft 19 is input to the data acquisition device 29 via the frequency-voltage converter 26 The value is calculated by the ECU 21 to determine the fuel injection timing of the first cylinder 11a, and at the same time as the fuel injection timing to the first cylinder 11a, the ECU 21 causes the corresponding fuel injection valve ( 14) and the first skip step (S-2) to prevent fuel injection and combustion of fuel to the first cylinder 11a by turning off the switches 17 and 18 connected to the spark plug 15. Through this, instead of generating combustion of fuel in the interior of the first cylinder 11a, the combustion chamber temperature of the first cylinder 11a is increased by a predetermined temperature by heat of compression of air by the piston.

After the first skip step (S-2) as described above, the pulse generated from the encoder 20 in accordance with the rotation of the cam shaft 19 is input to the data acquisition device 29 via the frequency-voltage converter 26. The calculated data value is calculated by the ECU 21 to determine the fuel injection timing of the third cylinder 11c and at the same time as the fuel injection timing to the third cylinder 11c, the ECU 21 supplies the corresponding fuel injection. The first fuel injection step (S) which enables fuel injection and combustion of the fuel to the third cylinder 11c by turning on the switches 17 and 18 connected to the valve 14 and the spark plug 15. -3), thereby generating an initial driving force for the operation of the engine (10).

After the first fuel injection step (S-3) as described above, the pulse generated from the encoder 20 in accordance with the rotation of the cam shaft 19 is passed to the data acquisition device 29 via the frequency-voltage converter 26. The ECU 21 determines the fuel injection timing of the fourth cylinder 11d by arithmetic processing of the input data value at the ECU 21 and at the same time as the fuel injection timing to the fourth cylinder 11d. The second skip step for preventing fuel injection and combustion of fuel to the fourth cylinder 11d by turning off the switches 17 and 18 connected to the injection valve 14 and the spark plug 15 ( S-4), which causes the combustion chamber temperature of the fourth cylinder 11d to be increased by a predetermined temperature due to the heat of compression of the air by the piston instead of the combustion of fuel in the fourth cylinder 11d. .

After the second skip step (S-4) as described above, the pulse generated from the encoder 20 in accordance with the rotation of the cam shaft 19 is input to the data acquisition device 29 via the frequency-voltage converter 26. The calculated data value is calculated by the ECU 21 to determine the fuel injection timing of the second cylinder 11b and at the same time as the fuel injection timing to the second cylinder 11b, the ECU 21 supplies the corresponding fuel injection. The second fuel injection step (S) which causes fuel injection and combustion of the fuel to the second cylinder 11b by turning ON the switches 17 and 18 connected to the valve 14 and the spark plug 15. -5), thereby generating an additional driving force for the operation of the engine 10 together with the first fuel injection step (S-3).

As described above, the step of setting the fuel skip cycle SC including the first skip step S-2 to the second fuel injection step S-5 according to the initial start of the vehicle, that is, cold start or restart by idle stop. By carrying out once to three times from (S-1), the combustion chamber temperature of the 1st cylinder 11a and the 4th cylinder 11d is made to rise by a fixed temperature by the heat of compression of air, and then ECU 21 Through the cylinder 11 is made of a configuration such that the injection and combustion of the normal fuel, such as a general engine cycle occurs into.

In order to confirm the effect of reducing the emission of unburned hydrocarbons by applying the start control method according to the present invention having the above-described configuration to the engine cycle, a normal fuel injection condition for each coolant temperature is a no-skip cycle. 6 and 9 show the results of measuring the emission concentrations of unburned hydrocarbons by applying one fuel skip cycle SC and three fuel skip cycles SC according to the present invention.

FIG. 6 shows the discharge of unburned hydrocarbon (HC) according to a normal start (0 skip) and a skip start (1 skip) (3 skip) of the present invention under a condition of a coolant temperature of 30 ° C., that is, similar to the initial (cold) start of the vehicle. As a result of comparing and analyzing the concentration, as shown in the figure, it can be seen that it is a super-tool that shows a large change in the air-fuel ratio for about 1 second after starting, and then the equivalence ratio is changed from about 1.6 to 1.4 with slight variation. It can be seen that gradually decreases.

In addition, under normal starting conditions (0 skip), the concentration of unburned hydrocarbons HC discharged from the exhaust manifold 16 in a section between 1 second and 1.5 seconds after starting is caused by incomplete combustion generated inside the cylinder 11. The highest concentration was 130,000 ppm, and since then, the exhaust concentration of unburned hydrocarbon (HC) is up to about 20,000 ppm to 10,000 ppm due to the temperature increase of the inner wall of the cylinder (11) due to the continuous operation of the engine (10). It can be seen that the decrease.

However, when the fuel skip cycle SC according to the present invention is applied once (1 skip), the concentration of unburned hydrocarbons HC discharged from the exhaust manifold 16 is increased in the interval between 1 second and 1.5 seconds after starting. It is reduced to the level of 15,000 ppm to 10,000 ppm, and after 2 seconds, the emission concentration of unburned hydrocarbon (HC) is lower than the normal starting condition, and in particular, the fuel skip cycle (SC) according to the present invention is performed three times. In case of application (3 skips), it can be seen that the emission concentration of unburned hydrocarbon (HC) discharged to the exhaust manifold 16 after start-up is lower than 10,000 ppm, which is lower than the previous two conditions.

7 shows a general start (0 skip) and a skip start (1 skip) (3 skip) of the present invention under a condition of a coolant temperature of 50 ° C., i. As a result of the comparative analysis of the emission concentration of unburned hydrocarbons (HC) according to the results, it can be seen that about 0.8 seconds after starting, it is an over-the-large tool with a large change in air-fuel ratio, and after a slight fluctuation, the equivalent ratio It can be seen that the Equivalence Rate is gradually reduced from about 1.5 to 1.3.

In addition, under normal starting conditions (0 skip), the concentration of unburned hydrocarbons HC discharged from the exhaust manifold 16 in a section between 1 second and 1.5 seconds after starting is caused by incomplete combustion generated inside the cylinder 11. 50,000 ppm ~ 20,000 ppm, and since then the temperature rise of the inner wall of the cylinder (11) in accordance with the continuous operation of the engine 10, the concentration of unburned hydrocarbons (HC) up to about 15,000 ppm ~ 10,000 ppm It can be seen that the decrease to the level of.

However, when the fuel skip cycle (SC) according to the present invention is applied once (1 Skip), the level of unburned hydrocarbon (HC) discharged through the exhaust manifold 16 from 1.2 seconds after starting is about 10,000 ppm. In the case of applying three times the fuel skip cycle (SC) according to the present invention (3 Skip), unburned hydrocarbon (HC) discharged from the exhaust manifold 16 is shown. Although the concentration of is slightly fluctuating, it can be seen that since 1.7 seconds after starting, the level is lower than 10,000 ppm which is much lower than the normal starting condition.

FIG. 8 shows a general start (0 skip) and a skip start (1 skip) of the present invention under a condition similar to that of a coolant temperature of 70 ° C., that is, a vehicle is started and restarted after an idle stop. As a result of comparing and analyzing the emission concentration of unburned hydrocarbon (HC) according to 3 skip), it can be seen that it is an over-the-large tool with a large change in air-fuel ratio for about 0.8 seconds after starting, as shown in FIG. It can be seen that the equivalence ratio gradually decreases from about 1.5 to 1.3 as it goes through.

In addition, under a general starting condition (0 skip), the concentration of unburned hydrocarbon (HC) discharged from the exhaust manifold 16 in a section between 1 second and 2.5 seconds after starting is about 30,000 ppm to 15,000 ppm. Since then, it can be seen that the emission concentration of unburned hydrocarbons (HC) is reduced to a level of about 17,000 ppm to 10,000 ppm, and the fuel skip cycle (SC) according to the present invention is applied once (1 Skip). In addition, in the interval between 1.5 seconds and 3 seconds after starting, the concentration of unburned hydrocarbons (HC) discharged from the exhaust manifold 16 is about 30,000 ppm to 15,000 ppm, compared to the normal starting conditions. The emission reduction effect of the fuel cell was slightly reduced, and when the fuel skip cycle (SC) according to the present invention was applied three times (3 Skip), the concentration of unburned hydrocarbon (HC) discharged from the exhaust manifold 16 was increased. Slight fluctuation A look, but it can be seen that there appears a very lower than the normal start up as the level of 10,000 ppm or less Starting 1.4 seconds after the startup.

FIG. 9 shows a general start (0 skip) and a skip start (1 skip) of the present invention under a condition of a coolant temperature of 90 ° C., that is, a condition similar to that of restarting after an idle stop is performed in a state where the vehicle starts and the engine is sufficiently warmed up. As a result of comparing and analyzing the emission concentration of unburned hydrocarbons (HC) according to (3 skip), it can be seen that it is an over-the-large tool with a large change in air-fuel ratio for about 0.9 seconds after starting, as shown in FIG. It can be seen that the equivalence ratio gradually decreases from about 1.6 to about 1.3 through.

In addition, under the general starting condition (0 skip), the concentration of unburned hydrocarbon (HC) discharged from the exhaust manifold 16 in the interval between 1 second and 3 seconds after starting is 30,000 ppm to 20,000 ppm. Since then, it can be seen that the emission concentration of unburned hydrocarbons (HC) is reduced to a level of about 17,000 ppm to 10,000 ppm, and the fuel skip cycle (SC) according to the present invention is applied once (1 Skip). In the range of 2 to 3.5 seconds after starting, the concentration of unburned hydrocarbon (HC) emitted from the exhaust manifold 16 is about 25,000 ppm to 10,000 ppm. In the case where the fuel skip cycle SC according to the present invention is applied three times (3 skips), although the concentration of unburned hydrocarbons HC discharged from the exhaust manifold 16 shows slight fluctuation characteristics, , After startup 1. It can be seen that from 4 seconds, the level is less than 6,000 ppm, which is much lower than during normal startup.

As described above, the results of measuring the concentration of unburned hydrocarbons (HC) by applying a no-skip cycle, which is a normal fuel injection condition, and a fuel skip cycle (SC) according to the present invention for each cooling water temperature, are shown. As can be seen in the graph of FIG. 10, when the coolant temperature is 30 ° C., when the fuel skip cycle (SC) of the present invention is applied once (1 skip) as compared with a normal start (0 skip), unburned hydrocarbon When HC emissions are reduced by about 38% and three fuel skip cycles (3 skips), emissions of unburned hydrocarbons (HC) are significantly reduced by about 63.8%.

When the coolant temperature is 50 ° C, one fuel skip cycle SC is applied (1 skip) as compared to the normal start (0 skip). In the case of application (3 skips), the emission of unburned hydrocarbons (HC) was reduced by about 38.7%, and when one coolant cycle (SC) was applied (1 skip) when the coolant temperature was 70 ° C Compared with, the emissions of unburned hydrocarbons (HC) were hardly reduced, but when three fuel skip cycles (SC) were applied (3 skips), the emissions of unburned hydrocarbons (HC) decreased by about 48%. When the temperature is 90 ℃, one fuel skip cycle (SC) is about 46%, and three fuel skip cycles (SC) are about 57%. It can be seen that the emissions of unburned hydrocarbons (HC) are significantly reduced compared to the start-up. .

In addition, in the present invention, the fuel skip cycle (SC) is applied only once to three times from the initial start of the vehicle. The reason for considering the emission reduction effect of unburned hydrocarbon (HC) and the starting delay of the vehicle at the same time, fuel The skip cycle (SC) must be applied at least once from the initial start of the car to obtain the effect of reducing the emission of unburned hydrocarbons (HC) compared to the normal start-up. It is not preferable to consider the emission reduction effect of (HC) and the start delay of the vehicle at the same time. Therefore, the application frequency of the fuel skip cycle (SC) is preferably limited to at least one to three times from the start of the vehicle. Do.

As described above, although the start control method according to the present invention is applied to a four-cylinder gasoline engine, the fuel is skipped to the first cylinder 11a and the fourth cylinder 11d, but the second cylinder 11b and the first cylinder are used. The same effect can be obtained by applying the fuel skip to the three-cylinder (11c) .In the case of three- and six-cylinder gasoline engines, only the number of cylinders is different. In accordance with the start control method of the present invention, if the fuel injection to each cylinder is skipped, the same effect as the present invention can be obtained, and in the case of three-, four- and six-cylinder diesel engines, each cylinder forming a diesel engine It is possible to obtain the same effect as the present invention if only the fuel injection to the inside of the skip is achieved to those of ordinary skill in the art. It's true that Ji Yong-yong is true.

<Driving test mode test result>

Hereinafter, the driving test mode test results of the present invention will be described in detail.

The test is to test the present invention in accordance with the driving test mode of the vehicle prescribed in the United States, Europe, Japan, Korea and the like.

The driving test modes of the vehicle include the FTP72 and FTP75 in the US, the ECE / EG in Europe, and the 11- and 10-mode Tokyo in Japan.

In the US, the FTP72 and FTP75 modes are 1 cycle per test. The test is completed. The driving distance is 12.1km and 17.9km, and the average driving speed is 31 ~ 34km / h and the maximum speed is 91.2km / h. The idle rate during the test process is 17.9%, but the short pause time does not have a significant effect on fuel saving and emission reduction when the idle stop function is applied.

On the other hand, in the case of European ECE / EG and Japanese 11- and 10-modes, the test cycle is repeated four times per test.

In Europe, the ECE / EG has a very short driving distance of 1.0km, an average driving speed of 18.7 km / h, and a maximum speed of 50km / h, which is slower than the FTP mode.

On the other hand, idling accounts for 31% of the test time, which is the largest idle period compared to other test modes.

In Japan's 11- and 10-mode Tokyo, the mileage is 1.0 and 0.7km. The average speed is 30.6km / h and 17.7km / h, and the maximum speed is 60km / h and 40km / h. The idling rate is 21.7% and 26.7% during one test time. The characteristics of each of these test modes are shown in Table 3 below.

Prescribed Test Mode FTP72 FTP75 ECE / EG 11-mode 10-mode Mileage (km) 12.1 17.9 1.0 1.0 0.7 Travel average speed (km / h) 31.7 34.1 18.7 30.6 17.7 Speed (km / h) 91.2 91.2 50.0 60.0 40.0 Idle rate (%) 17.9 17.9 31.0 21.7 26.7 Cycles per test One One 4 4 4 Applicable Country United States of America United States of America Europe Japan Japan

[CVS 75 Test Cycle]

The FTP 75 test cycle shows the driving speed patterns of representative cars measured in the US during the morning commute to Los Angeles, and consists of three test sections.

Section 1 is the cold phase for 0 to 505 seconds, and Section 2 is the stabilized phase for 505 to 1,372 seconds. After the engine was turned off for 10 minutes, three hot phases took place between 1,972 and 2,477 seconds.

The test of the vehicle is carried out after parking for more than 12 hours in the test room where the room temperature is 20 ~ 30 ℃, and the driving test is performed in accordance with the prescribed driving line immediately after starting.

During the cooling section, the exhaust gas of the car is diluted and collected in the bag 1, and the exhaust gas is collected in the bag 2 from 505 seconds when the safety section starts to 1,371 seconds when the engine is turned off. After the 10-minute stop, the engine starts three sections for 505 seconds at the same time as the engine is restarted.

The bag 1 and bag 2 are analyzed immediately at the end of section 2 according to the regulation that the exhaust gas probe should not be exposed in the bag for more than 20 minutes.

The sum of the weights of HC, CO and NOx, the representative pollutants of the exhaust gases analyzed from the three bags, is expressed as the emissions per mileage.

Table 4 below shows the limits for vehicle emissions under the FTP75 test cycle in the US and California.

Model year Area of application CO (g / mile) HC (g / mile) NOx (g / mile) Boil off gas (g / test) 1982 to US California 3.417.0 0.410.41 1.00.4 2.02.0 1993 California 3.4 0.25 0.4 2.0 1994 U.S. Federal 3.4 0.25 0.4 2.0

The driving characteristics of the CVS 75 mode are used in Korea, which is quite different from the urban driving pattern in Korea.

The CVS 75 consists of a cold phase for 505 seconds, a stabilized phase for 867 seconds, a 10 minute stop, and a hot phase for 505 seconds.

The conditions of the vehicle measured by the CVS 75 test were tested on a base vehicle, a vehicle with an HC absorber, and a control mode 1 vehicle with an ASG (Auto Stop and Go) system of the present invention. The measurement results for each condition are shown in Table 5 below.

Type of test vehicle CO (g / km) NOx (g / km) NMHC (g / km) CO ₂ (g / km) Fuel Consumption (km / l ) Passed allowance 2.11 or less 0.19 or less 0.062 or less Basic vehicle Ph1 0.61 0.38 0.238 211.5 10.99 Pass Ph2 0.11 0.04 0.003 213.0 10.99 Ph3 0.41 0.06 0.013 183.0 12.75 Total 0.30 0.11 0.055 204.4 11.41 HCAdsorber Attachment Ph1 0.57 0.28 0.160 219.8 10.59 Pass Ph2 0.21 0.00 0.027 218.5 10.70 Ph3 0.36 0.01 0.037 187.6 12.44 Total 0.32 0.06 0.057 210.2 11.11 Improvement compared to base (%) -6.7 45.5 3.6 -2.8 -2.6 ASG attachment control mode 1 Ph1 0.93 0.40 0.236 199.9 11.59 Pass Ph2 1.81 0.01 0.010 200.2 11.53 Ph3 1.20 0.07 0.022 178.2 13.00 Total 1.46 0.11 0.060 194.1 11.91 Improvement compared to base (%) -387 0 -0.9 5.0 4.4

The basic conditions of three types of vehicle tests, with HC absorber and control mode 1 with ASG system, are CO (2.11g / km or less), NOx (0.19g / km or less), NMHC ( 0.062g / km or less) was confirmed as a vehicle that can operate in the country.

Control mode 1 of the ASG-equipped vehicle activates the idle stop function and skips fuel injection for two cycles in two of the four cylinders of the engine upon restart.

In the case of this vehicle, HC, CO, etc. are generated a lot, so it may be very difficult to satisfy the NMHC regulation value.However, it is understood that HC is not generated by the 3-cycle fuel injection skip function during restart. have.

Based on the basic vehicle, vehicles with HC absorbers emit 6% and 4% of CO and NMHC, and fuel economy is also lowered by 3%, indicating no advantage of vehicles with HC absorbers.

Control mode 1 of ASG-equipped vehicles has the same level of NOx and 9% more NMHC than the basic vehicle.

However, fuel economy improved 4.4 percent over the base vehicle.

In the case of CVS 75, the idle stop time in the test section was very short, so the effect of idle stop was not significant. However, the driving conditions in urban centers of Korea are expected to be greater than the CVS 75, since the idle time is considerably greater when the vehicle is stopped by traffic lights.

11 to 16 are graphs comparing the results of Table 5 with each measurement.

In the comparison graph of CO measurement of FIG. 11, in the case of the basic condition and the HC absorber attachment, the CO emission was the highest at Ph1 and the CO emission was low at Ph2, whereas the control mode 1 with ASG had the highest CO emission at Ph2 and the CO emission at Ph1. This is the least emitted.

The control mode 1 with ASG features the engine off in the idle section and restarts at the acceleration point after the idle section ends so that the ECU can inject a lot of fuel to supply the excess mixer due to the certainty of the starting. do.

In this case, even in a condition where the catalyst temperature is sufficiently high, the purification is almost impossible because the catalyst is out of the purification zone, and the emission of CO is difficult to adjust.

Therefore, in case of ASG-attached control mode 1, the emission of CO is inevitably higher than in other conditions. However, the measured CO measurements by the type of test vehicle satisfy all the below 2.11g / km CO2 emission limit of CVS 75.

12 compares the measured values of NOx measured for each test vehicle. Overall, the highest NOx emissions are found in Ph1 and the lowest emissions in Ph2, and they are all within the NOx emission limit of 0.19 g / km.

FIG. 13 compares the measured values of NMHC measured for each test vehicle. FIG. Overall, NMHC emissions are highest at Ph1 and lowest at Ph2, while ASG-equipped vehicles have the lowest at Ph3.

NMHC is the exhaust gas that is most related to the warm-up of the engine. In case of the control mode 1 with ASG, the engine is stopped and restarted in the idle section at all times. .

All vehicle conditions meet the CVS 75's NMHC emission allowance of less than 0.062 g / km.

14 compares the measured values of CO ₂ measured for each test vehicle. The many Overall emissions of CO ₂ in the Ph1 and the lowest emissions in Ph3.

CO ₂ emissions, which is the fuel economy of the engine and directly related to the case of ASG attached control mode 1, so always stop and restart the engine at idle period has shown the most improved vehicle fuel efficiency characteristics compared to other conditions. In CVS 75 mode there is no restriction on CO ₂ .

FIG. 15 compares fuel economy (FE) values of each test vehicle with measurements of CO ₂ . In case of ASG control mode 1, fuel efficiency was improved by 4.4% and CO ₂ was reduced by 5% compared to the basic vehicle.

On the other hand, vehicles with HC absorbers exhibited 2.6% lower fuel economy and 2.8% CO ₂ than those of the basic vehicle.

FIG. 16 is a graph showing emission gas measurements of each test vehicle with reference to the vehicle emission gas allowance of CVS 75.

The emission allowance for CO is 2.11g / km, but 0.30g / km for basic vehicles, 0.32g / km for vehicles with HC absorbers, and 1.46g / km for control mode 1 with ASG. Is showing.

In the case of NOx, the discharge allowance is 0.19g / km or less, but in the case of the basic vehicle, 0.11g / km, 0.06g / km in the case of HC absorber and 0.11g / km in the control mode 1 with ASG. It shows that it is passing.

The emission allowance for NMHC is 0.062g / km or less, but for basic vehicles, 0.055g / km, for vehicles with HC absorbers, 0.057g / km, and for control mode 1 with ASG, 0.060g / km. It shows that there is almost no passage.

According to the CVS 75 test regulations in Korea, vehicle inspections other than new vehicle certification are required to undergo defect identification inspection. In this case, each of the test vehicles conducted was authorized to operate through all the CVS 75 emission allowances.

In particular, in case of ASG control mode 1, fuel economy was improved by 4.4% compared to the basic vehicle.

[ECE15 + EUCE Test Cycle]

Next, the ECE / EG cycle is a driving speed pattern based on the driver's driving pattern in the city.

The ECE test cycle is applied in Belgium, Denmark, France, Germany, the United Kingdom, Greece, Ireland, Italy, Luxembourg, the Netherlands, Portugal and Spain. The test cycle starts the vehicle after a warm-up period of 40 seconds starting a car parked for more than 12 hours in a laboratory with a room temperature of 20 to 30 ° C.

This cycle completes one cycle by repeating four driving patterns with a cycle distance of 1.013 km. During the test period, the exhaust gases are collected in the same sample bag and analyzed.

Recently, the test mode of the vehicle has been changed from ECE / EG mode to ECE15 + EUDC mode, which is composed of a total of 11km mileage with the addition of the high speed mode to the ECE / EG test mode. It is applied in the test mode of EURO3.

Table 5 below shows the limit values for automobile emissions by the ECE / EG test cycle.

Engine displacement (l) Regulation CO (g / test) HC + NOx (g / test) NOx (g / test) 2.0 or higher 88/76 / EWG 25 6.5 3.5 1.4-2.0 88/76 / EWG 30 8 1.4 or less 88/76 / EWG89 / 458 / EWG 4519 155 6 All emissionsECE15 + EUDC 91/441 / EWG 2.72g / km 0.79g / km

The ECE15 + EUDC mode has a 31% idle rate compared to the 17.9% idle rate of the CVS 75 mode.

The idle time is 11 seconds, 21 seconds, and 21 idle cycles for the first cycle, and 18 seconds, 21 seconds, and 21 seconds idle cycles for the second to fourth cycles.

Therefore, it was judged that the time in the idling section could improve the emission gas and fuel economy of the idling stop function. Table 7 below shows the vehicle test results obtained by the ECE15 + EUDC mode.

This test was carried out as a certification test, and the same test was performed twice in succession, and when the number of measurements for each number exists within 3% of each other, it is a very reliable test that judges that the test was performed within the reliability range.

Type of test vehicle CO (g / km) NOx (g / km) NMHC (g / km) CO ₂ (g / km) Fuel Consumption (km / L) Tolerance (g / test) Pass or not CO (less than 30) HC + NOx (8 or less) Base vehicle Ph1 3.82 0.49 0.640 265.8  8.55 15.82 4.822 O Ph2 0.05 0.03 0.008 161.5 14.50 Total 1.44 0.20 0.241 199.9 11.54 HCAdsorber Attachment Ph1 0.94 0.25 0.293 287  8.09 10.72 2.27 O Ph2 1.00 0.00 0.009 164.4 14.11 Total 0.98 0.09 0.114 230.4 11.07 Improvement compared to base (%) 31.9 55 53 -15.3 -4.1 ASG attachment control mode 0 Ph1 7.18 0.55 0.624 239.5  9.26 48.74 5.75 Ⅹ Ph2 2.83 0.08 0.058 158.9 14.32 Total 4.43 0.26 0.266 188.6 11.92 Improvement compared to base (%) -209 -30 -10.4 5.7 3.3 ASG attachment control mode 1 Ph1 6.09 0.64 0.605 233.9  9.54 27.29 5.32 O Ph2 0.36 0.02 0.015 159 14.68 Total 2.48 0.25 0.233 186.7 12.24 Improvement compared to base (%) -72 -25 3.3 6.6 6.1 Improvement compared to control 0 (%) 44 3.8 12.4 1.0 2.6

17 to 22 are graphs comparing the results of Table 7 with each measurement.

Ph1 represents a city driving pattern and Ph2 represents a highway driving pattern. The measurement results of the test vehicle need to be mainly focused on the results of Ph1. In addition, each measurement is expressed in g / km for the emission gas, but the car emission limit is expressed in 30g / test for CO and 8g / test for HC + NOx.

In the comparison graph of CO measurement value of FIG. 17, in the case of the control mode 0 and the control mode 1 with ASG, the CO emission was high at Ph 1 and the CO emission was low at Ph 2, whereas with HC absorber, CO emission was high at Ph 2. There is less CO emission from Ph1.

The control mode 0 and control mode 1 feature of the ASG is turned off at the idle section and restarted at the acceleration point after the idle section is finished. It will inject a lot of fuel for the mixer supply

In this case, even in a condition where the catalyst temperature is sufficiently high, the purification is almost impossible because the catalyst is out of the purification zone, and the emission of CO is difficult to adjust.

Therefore, in case of the control mode 0 and the control mode 1 with ASG, the emission of CO is inevitably higher than that in the other conditions.

18 compares the measured values of NOx measured for each test vehicle. In general, NOx is the highest in Ph1 and the lowest in Ph2.

19 compares the measured values of NMHC measured for each test vehicle. Overall, NMHC emissions are highest at Ph1 and lowest at Ph2.

In the case of NMHC emission in Ph1, the basic vehicle emits the most as 0.64g / km, 0.624g / km in ASG control mode 0, 0.605g / km in ASG control mode 1, HC absorber attached. In the case of vehicles, the lowest NMHC emissions are 0.293. In the ECE15 + EUDC mode, the idle time is longer than that in the CVS75 mode, which shows that the emission reduction effect due to the idle stop is significantly increased.

20 compares the measured values of CO ₂ measured for each test vehicle. When the discharge amount of CO ₂ in Ph1 Ph1 and in the case of the HC adsorption attachment vehicle is most discharged to 287g / km, if the base vehicle of 265.8g / km, ASG adhesion control mode 0 239.5g / km and ASG for adhesion control mode 1 is being discharged to the least CO ₂ as 233.9g / km. This also ECE15 + EUDC mode, it can be seen that the reduction in the exhaust gas due to idle stop at the time of the idle interval than CVS 75 mode significantly increases CO ₂ appears.

21 compares the fuel economy and CO ₂ measured values of each test vehicle. In case of ASG control mode 1, fuel efficiency was improved by 6.1% and CO ₂ was reduced by 6.6% compared to the basic vehicle.

In addition, in case of ASG control mode 0, fuel efficiency was improved by 3.3% and CO ₂ was reduced by 5.7% compared to the basic vehicle. Whereas HC absorbing groups attached to the vehicle fuel consumption as compared to the basic vehicle is 4.1%, CO ₂ is 15.3% degraded exhibits the characteristics, but is is very effective reduction of the effects of HC adsorption NMHC fuel efficiency and CO ₂ emission reduction effect does not appear at all It can be seen that.

Fig. 22 is a graph showing the measured emission values of each test vehicle with reference to the vehicle emission gas allowance of ECE15 + EUDC.

The emission allowance for CO is 30g / test, but 15.82g / test for basic vehicles, 10.72g / test for vehicles with HC absorbers, and 27.29g / test for ASG-controlled control mode 1, which passes the emission allowance sufficiently. It is showing.

However, in the control mode 0 with ASG, the emission of CO is 48.74 g / test, which is higher than the allowable value, which does not satisfy the regulation value. Control mode 0 with ASG applies the normal restart mode without fuel injection skip when restarting after idling in the idle section.

Judging from this, it was confirmed that the fuel injection skip must be applied when restarting to satisfy the vehicle emission allowance in the regulation mode.

  In the case of HC + NOx, the discharge allowance is 8g / test or less, but 4.822 g / test for the basic vehicle, 2.27 g / test for the vehicle with HC absorber, 5.75 g / test for the control mode with ASG, and control mode with ASG In case of 1, it is 5.32 g / test, which shows that the emission allowance is sufficiently passed.

[Modal test]

Although the reliability is slightly lower than the ECE15 + EUDC mode certification test, there is a modal test to analyze the degree of emission per hour.

The measured value of this modal test can measure all the exhaust gas per second in the test section and output the result, which has the advantage of analyzing the characteristics of the exhaust gas generated in each driving section in the driving mode.

As a modal test, the control mode 2 and control mode 3 test with the basic vehicle, ASG was performed. The results are shown in Table 8 below.

Control mode 2 operates when the coolant temperature is above 65 ℃, and skips fuel injection for 3 cycles when restarting. Control mode 3 operates in the same way as control mode 2, but Ph1 in ECE15 + EUDC mode. This is the control mode in which the idle stop function is activated in the first of four cycles.

23 to 29 are graphs comparing Table 8 results with each measurement.

Comparing Table 7 with that of the basic vehicle shows that the results are quite different.

This is influenced by the amount of fuel used and the fuel consumption due to the operation of the vehicle and the state of the vehicle during the test. Therefore, if the test measurement result of the basic vehicle is different during the test, the vehicle test related to this is also difficult to newly measure.

In this modal test, three basic vehicle tests were conducted to ensure the reliability of the data. The results of these three tests were significantly different from those of the basic vehicle in Table 8, so that the related control mode 2 and control mode 3 The test was newly measured.

The control mode 2 is to operate the ASG function based on the coolant temperature of 65 ° C. The ASG function is activated from almost the third of the four cycles constituting Ph1 in the ECE15 + EUDC mode.

The control mode 3 is the control mode in which the ASG function is activated in the first cycle among the four cycles constituting Ph1, the ASG function is not activated in the second cycle, and the ASG function is restarted from the third cycle.

Type of test vehicle CO (g / km) NOx (g / km) NMHC (g / km) CO ₂ (g / km) Fuel Consumption (km / L) Tolerance (g / test) Pass or not CO (less than 30) HC + NOx (8 or less) Base vehicle Ph1 1.90 0.44 0.595 282.4  8.15 8.26 4.425 O Ph2 0.08 0.02 0.010 159.7 14.65 Total 0.75 0.18 0.225 205.0 11.32 ASG attachment control mode 2 Ph1 3.21 0.40 0.520 267.7 8.53 15.19 3.955 O Ph2 0.32 0.02 0.017 159.4 14.65 Total 1.38 0.16 0.202 199.1 11.60 Improvement compared to base (%) -84 11.1 10.2 2.9 2.5 ASG attachment control mode 3 Ph1 5.18 0.52 0.75 255.1  8.82 23.1 5.406 O Ph2 0.29 0.02 0.017 158.6 14.72 Total 2.10 0.20 0.289 194.3 11.80 Improvement compared to base (%) -180 -20 -28.4 5.2 4.2

In the comparison graph of the CO measurement value of FIG. 23, the basic condition and the condition of the control mode 2 with the ASG are the areas in which the first two cycles of the four cycles constituting Ph1 are operated in the same manner. On the other hand, in case of control mode 3, the ASG function is operated in the remaining three cycles except for the second cycle of Ph1.

24 compares the measured values of NOx measured for each test vehicle. As control mode 2 emits the least NOx, it can be seen that the emission reduction effect of NOx is shown in comparison with the basic vehicle.

FIG. 25 compares the measured values of NMHC measured for each test vehicle. FIG. The emission of NMHC is very important. Control mode 2 emits the least NMHC and the emission reduction effect of NMHC is much higher than that of the basic vehicle. On the other hand, in case of the control mode 3, the NMHC emits more than the basic vehicle.

NMHC emissions from Ph1 are 0.75g / km in ASG with control mode 3, which emits the most NMHC, while 0.595g / km in ASG is 0.520g in control mode 2 with ASG. The smallest NMHC emissions per kilometer.

In case of control mode 2 with ASG, NMHC reduction effect was about 12.6%.

FIG. 26 compares the measured values of CO ₂ measured for each test vehicle.

When the discharge amount of CO ₂ in Ph1 Ph1 in a case when the basic vehicle 282.4g / km, the ASG adhesion control mode 2 267.7g / km and ASG adhesion control mode 3 is the least CO ₂ as 255.1g / km It is being discharged. This also ECE15 + EUDC mode, it can be seen that the reduction in the exhaust gas due to idle stop at the time of the idle interval than CVS 75 mode significantly increases CO ₂ appears.

Fig. 27 compares the measured values of fuel efficiency of each test vehicle. This shows that the fuel economy reduction effect in Ph2 is hardly shown, while the fuel efficiency improvement effect in Ph1 has a great influence on the overall fuel efficiency effect. It can be seen that the fuel efficiency effect of the ASG attached control mode 3 is greater than that of the other two cases.

FIG. 28 compares fuel consumption and CO ₂ measured values of each test vehicle. FIG. In case of ASG with control mode 2, fuel efficiency was improved by 2.5% and CO ₂ was reduced by 2.9% compared to the basic vehicle. In addition, in case of ASG control mode 3, fuel efficiency was improved by 4.2% and CO ₂ was reduced by 5.2% compared to the basic vehicle.

Fig. 29 is a graph showing the measured emission values of each test vehicle with reference to the vehicle emission allowance of ECE15 + EUDC.

In the case of CO, the discharge allowance is 30g / test, but 8.26g / test in the basic vehicle, 15.19g / test in the control mode 2 with ASG, and 23.1g / test in the control mode 3 with ASG. It is showing.

For HC + NOx, the discharge allowance is 8g / test or less, but 4.425 g / test for the basic vehicle, 3.955 g / test for the control mode 2 with ASG, and 5.406 g / test for the control mode 3 with ASG. It shows that it passes enough.

Comparing the basic vehicle with the control mode 2 shows a satisfactory result in the control mode 2 with 11.1% NOx, 10.2% for NMHC, 2.9% for CO ₂ and 2.5% for CO2. It was.

In the case of CO, only about 50% of the emission allowance of 30g / test is emitted, but the emission is about 83% higher than that of the basic vehicle, and the improvement is considered.

On the other hand, when comparing the basic vehicle and the control mode 3, the control mode 3 showed more emissions than the base vehicle in the case of CO, NOx, and NMHC, and showed only 5.2% increase in CO ₂ and 4.2% in fuel economy. It was.

As a result, it was confirmed that the future ASG control mode should apply the fuel injection skip control mode in conjunction with the coolant temperature to apply the optimum control mode 2 to improve the fuel consumption while improving the atmospheric environment.

As described above, the vehicle start control method for reducing the emission of harmful gases including unburned hydrocarbon according to the present invention, each of the engine cycle in the process of operating one to three times from the start of the engine at the initial start or idle stop start of the car The fuel injection into the cylinder is skipped, and the internal temperature of the cylinder in which no fuel is injected is preheated by the heat of compression by the piston, and thus the internal temperature of the cylinder is heated to a predetermined temperature. By making a normal fuel injection into the cylinder, it is possible to reduce the emissions of harmful gases, including unburned hydrocarbons, which are generated due to incomplete combustion of fuel during initial start-up and idle stop start-up of an automobile engine.

1 is a schematic diagram of a tandem engine

2 is a schematic diagram of a V engine

3 is a schematic diagram of an opposing engine

Figure 4 is a schematic diagram showing an experimental apparatus applied to the control method of the present invention.

5 is a flowchart showing a control method of the present invention.

FIG. 6 is a graph showing a result of applying a fuel skip cycle under a coolant temperature of 30 ° C. FIG.

7 is a graph showing a result of applying a fuel skip cycle under a coolant temperature of 50 ° C.

8 is a graph showing a result of applying a fuel skip cycle under a coolant temperature of 70 ° C.

9 is a graph showing a result of applying a fuel skip cycle under a coolant temperature of 90 ° C.

10 is a graph showing the effect of reducing the emissions of unburned hydrocarbons according to the control method of the present invention.

11 is a graph comparing the CO measurements in the CVS 75 test mode.

12 is a graph comparing NO _x measurements in the CVS 75 test mode.

13 is a graph comparing NMHC measurements in CVS 75 test mode.

14 is a graph comparing CO ₂ measurements in the CVS 75 test mode.

15 is a graph comparing FE and CO ₂ measurements in the CVS 75 test mode.

Fig. 16 is a graph comparing the measured emission values and the allowable values in the CVS 75 test mode.

17 is a graph comparing CO measurements in the ECE15 + EUDC test mode.

18 is a graph comparing the NO _X measurements in the ECE15 + EUDC test mode.

19 is a graph comparing NMHC measurements in ECE15 + EUDC test mode.

20 is a graph comparing the CO ₂ measurements in the ECE15 + EUDC test mode.

21 is a graph comparing FE and CO ₂ measurements in the ECE15 + EUDC test mode.

22 is a graph comparing emission values and allowable values in the ECE15 + EUDC test mode.

23 is a graph comparing the CO measurements in the modal test mode

24 is a graph comparing the NO _x measurement in the modal test mode

25 is a graph comparing NMHC measurements in modal test mode.

26 is a graph comparing CO ₂ measurements in a modal test mode.

27 is a graph comparing the F.E. measurements in the modal test mode.

28 is a graph comparing FE and CO ₂ measurements in a modal test mode.

29 is a graph comparing emission values and allowable values in a modal test mode.

<Explanation of symbols for main parts of drawing>

10 engine 11 cylinder 12 fuel tank

13 fuel supply pipe 14 fuel injection valve 15 spark plug

16 Exhaust Manifold 17 Valve Switch 18 Plug Switch

19: Camshaft 20: Encoder 21: ECU

22: air-fuel ratio sensor 23: piezoelectric pressure sensor 24: meter reading rod

25, 27, 28: amplifier 26: transducer 29: data acquisition device

S-1: setting step S-2: first skip step S-3: first fuel injection step

S-4: Second skip step S-5: Second fuel injection step SC: Fuel skip cycle

Claims (4)

In the start control method of the engine having several cylinders, the several cylinders are ignited in a predetermined ignition order to achieve a normal cycle, (a) determining a start or restart state of the engine; And and (b) repeating at least one or more fuel skip cycles in which ignition and skip are alternately performed according to the ignition order of the cylinder when the starting or restarting state is performed in step a. The start control method for a vehicle according to claim 1, wherein the skip is performed by stopping fuel supply to the cylinder. The start control method for a vehicle according to claim 1, wherein the ignition sequence begins with either ignition or skip. The start control method of a vehicle according to claim 1, wherein the fuel skip cycle is repeated one to three times.