KR101377129B1 - Engine analysis apparatus for compression ignition engine automobile - Google Patents

Abstract

The present invention relates to an engine analysis method and apparatus via the fuel injection amount analysis of a compression ignition engine vehicle, wherein the engine analysis apparatus receives the fuel injection amount signals or power/balance amount signals of a new vehicle control group (N), a malfunctioning vehicle control group (F), and a vehicle to be measured (T), respectively, and judges the engine state of the vehicle to be measured (T) by comparing and analyzing the distribution data of each fuel injection amount. The present invention can check and diagnose the engine state efficiently based on the basic operating principles and characteristics of the vehicle engine by only comparing and analyzing the fuel injection amount of the vehicle to be measured with the fuel injection amount data of the new vehicle control group (N) and the malfunctioning vehicle control group (F). [Reference numerals] (AA) Engine state analysis step; (S1) Sensor signal input step; (S10) Variation state analysis step; (S2) Step for measuring the fuel injection amount of a new vehicle; (S20) Normal distribution state analysis step; (S3) Step for measuring the fuel injection amount of a malfunctioning vehicle; (S30) Normal distribution frequency difference analysis step; (S4) Step for measuring the fuel injection amount of a vehicle to be measured; (S6) Analysis result display step

Description

Engine inspection analysis method and apparatus through fuel injection amount analysis of compression ignition engine vehicle {Engine Analysis Apparatus For Compression Ignition Engine AutoMobile}

The present invention relates to an engine inspection analysis method and apparatus through fuel injection amount analysis of a compression ignition engine vehicle, and inputs the respective fuel injection amount signals of the new vehicle control group (N), the faulty vehicle control group (F), and the measurement target vehicle (T). Receiving sensor signal input step (S1); New fuel injection amount measurement step (S2) of measuring the distribution data of the fuel injection amount (Sn) of the new vehicle control (N) by using the fuel injection amount signal; and, the fuel A fault difference fuel injection amount measurement step S3 of measuring distribution data of the fuel injection amount Sf of the fault difference control group F using the injection amount signal; and the measurement to be analyzed using the fuel injection amount signal A target vehicle fuel injection amount measuring step (S4) of measuring distribution data of fuel injection amount (St) of the target vehicle (T); and distribution data of the fuel injection amount (Sn) of the new vehicle control group (N) and the faulty vehicle control group ( F), fuel minutes An engine state analysis step (S5) of comparing the distribution data of the fuel injection amount St of the measurement target vehicle with respect to the distribution data of the dead amount Sf to determine the engine state of the measurement target vehicle T; An analysis result display step (S6) of displaying an engine state of the measurement target vehicle (T) analyzed through the state analysis step (S5); The present invention relates to an engine inspection analysis method and apparatus through fuel injection amount analysis of a compression ignition engine vehicle comprising a.

In general, diesel engines employ a common rail system for the purpose of reducing engine speed, high power, and fuel economy. In this system, an engine is mounted with an accelerometer in the center of the engine block. The signal is detected and analyzed every hour to adjust the pilot fuel amount according to the injector state of each cylinder.

In the diesel engine, the fuel injection device (injector) is opened or closed to block fuel by the carbon or to inject the fuel inlet fuel nozzle (nozzle) part to inject the fuel due to abrasion, etc. The mechanical parts, etc., which function are slowed down and the fuel supply is not desired, so the fuel supply amount tends to change, such as a decrease in the fuel injection amount. As a result, when fuel defects appear when they are left unattended, the more the vehicle travels, the more the injection quantity is caused by deterioration of smoke and deterioration in durability due to exhaust system degradation. On the contrary, when there is a low fuel deficiency, the engine speed of the fuel-low cylinder is reduced, and the fuel injection amount is increased to the injector mounted on the other cylinder as well as the injector mounted on the cylinder with the low engine rotation in order to achieve this. Let's go. Because in general, when there is little fuel injection in some cylinders, the rotation of other cylinder cylinders is slowed as well as a cylinder in which fuel injection is supplied by inertia. Thus, the ECU, an engine electronic computer, increases the fuel injection amount by a slower engine speed for a cylinder with a slow engine speed. However, when the degree of defects becomes severe, the increased fuel injection amount to evenly adjust the engine rotation becomes excessive, and the same phenomenon appears that the fuel is injected a lot (side effects of the fuel injection control function 1).

Therefore, side effects caused by the increase or decrease of the fuel injection amount are prevented, and the combustion chamber compression pressure is leaked due to the sealing failure such as the intake and exhaust valve of the engine or the compression ring for keeping the engine piston tight. In order to prevent the engine speed from being irregular for each cylinder due to mechanical factors such as slowing down, the fuel injection amount is repeatedly detected and analyzed under a certain condition (hereinafter, referred to as "learning"), and then some cylinders are over a certain reference time. If a certain amount is injected compared to other cylinders, the amount of fuel injected into the cylinder is increased by adding the amount of fuel injected into the cylinder (this is called a positive learning value). Value). It calculates the fuel injection amount, which is composed of "basic fuel injection amount value + fuel injection amount learning value + other fuel injection amount correction value (fuel injection amount adjustment value that is added or decreased only in the corresponding conditions for improving engine temperature / operation performance, etc.)". Is to make all cylinder values as uniform as possible.

Although there are many objectives to make the basic injection amounts of all cylinders uniform, this is because one of the most representative objects is applied as a ratio with respect to the basic injection amount values when calculating various correction values such as the other fuel injection amount correction values. That is, if there is no learning value, the basic fuel injection amount may show a large difference for each cylinder according to the engine state. In this case, various correction values applied using the basic fuel injection amount value generate a large difference. That is, it is possible to analyze the state of the engine according to the magnitude of the value of injecting by adding or subtracting a certain amount according to the engine state (hereinafter referred to as "learning value") so that the basic fuel amount calculated value is as identical as possible for each cylinder. For reference, the basic fuel injection amount is determined in each area (8X8 or 16X16 points) by dividing into 8-16 stages in consideration of engine speed and engine torque through the test in compression ignition engine. That is, since the initially set fuel injection amount fluctuates with increasing various operating conditions and operation periods, the fuel injection amount is corrected by applying a learning value to maintain an optimum fuel injection amount.

As described above, the fuel injection amount signal generated to control the fuel injection amount of the engine by an electronic device such as an engine control unit (ECU) generally has a relatively small width as shown in FIG. Although it has a relatively constant value, but as the engine ages or abnormalities, as shown in FIG. 3, the fuel injection quantity signal variation gradually increases, and the fault difference (generally, it is almost a failure state. In the case of making the normal engine difficult to operate by removing the injector of one cylinder among the cylinders of the engine), the value of the fuel injection quantity signal is very large as shown in FIG. The fuel injection quantity signal fluctuates with.

Therefore, if the distribution characteristic of the fuel injection amount signal is grasped, it may be possible to inspect / analyze the state of the engine.

On the other hand, in the common rail type diesel engine, the high pressure pump compresses the fuel to high pressure and supplies the fuel to the common rail, and the high pressure stored in the common rail (varies depending on the common rail system and is linked according to the engine speed and the accelerator pedal step amount). Up to 1600 bar) of fuel is supplied by the injector to the combustion chamber.

In the case of ignition combustion engines such as gasoline or LPG, the fuel supply amount is matched to the theoretical air-fuel ratio, so the fuel is supplied in accordance with the theoretical air-fuel ratio. Controlling the state is a limitation. Therefore, the ignition combustion engine is used to improve the engine condition such as adjusting the rotational force of the engine by adjusting the ignition timing.

On the other hand, in diesel engines compressed and ignited, the amount of air sucked into the engine is constant and there is no ignition system. Therefore, the factors that can control the rotational force of the engine are related to the fuel supply, such as fuel injection amount and fuel injection time. In this case, it is possible to apply the method to adjust the engine injection power by adjusting the fuel injection timing, but many experiments are necessary because the factors related to fuel injection timing (pre-injection / main injection / post injection) are combined. In order to reduce and increase the engine torque, it is necessary to set the fuel injection time as the reference fuel injection time when the fuel injection time is smaller than the point at which the maximum engine torque (torque) is generated, that is, the engine torque may increase when the injection time is increased. Under normal engine conditions, fuel should always be injected at the point of low engine torque. Therefore, the method of changing the fuel injection amount has been applied as a way to control the rotational speed change of each cylinder of the engine. After all, the function of controlling the engine torque by adjusting the fuel injection amount is applied to most diesel engines compression-ignition.

However, when the fuel injection amount is excessively adjusted to adjust the engine rotational force, soot is generated, which causes a large amount of fuel injection, and clogging due to carbon accumulation of the intake and exhaust system. Therefore, in the field of electronic control development, various methods (ie, limiting the amount of fuel injection by the number of engine revolutions) have been studied to minimize such side effects.

At this time, the injector is controlled by an engine control unit (ECU), and the engine control unit (ECU) is sensed by various sensors, and the driving timing of the injector according to the operation state such as the load degree, the rotation speed, etc. of the engine inputted. The opening time is controlled, and the injector executes pre-injection (Pi), main injection (Mi), and post injection according to the command.

In the diesel engine as described above, whether the injector is defective or not is referred to in various ways, such as fuel / compensation, rotational balance by cylinder, compression comparison by cylinder, and the like. Judging by measuring the amount) In other words, the fuel supply control valve of the high-pressure pump is fixed by fixing the engine speed determined by the engine oil (the engine speed is set for each vehicle from the idling reference speed to 2,000rpm and is usually the reference idling reference speed). If the fuel supply conditions for each cylinder are the same by fixing the fuel pressure, the fuel amount, the injection timing, and the injection time, and stopping the injectors one by one for each cylinder, there is no compression ignition explosion in the cylinder. The minimum rotational speed is 100% among the rotational speeds of each cylinder, and the value of power / balance is obtained by dividing the rotational speed of other cylinders by the percentage.

As another power balance test, the fuel supply control valve of the high pressure pump is fixed to fix the fuel pressure, injection timing, and injection time, so that the fuel supply conditions for each cylinder are the same, and the engine speeds determined by ISI oil are determined by each cylinder. The fuel injection time (injection amount) is adjusted so that the vehicle can be maintained at a standard idle speed from 2,000 rpm to the vehicle at normal idle speed. In other words, the amount of fuel injection for each cylinder required to rotate all cylinders at the reference idling speed, and the power balance amount is converted into a percentage of +/- relative to the occurrence of the difference with the average cylinder fuel amount.

Similarly to the fuel injection amount, the power balance amount also has a relatively constant value with a relatively small deviation in the case of a new car, but the deviation increases gradually with engine aging or abnormality, In the case of a difference, the power / balance amount fluctuates while the signal deviation is very large.

Therefore, if the distribution characteristic of the power / balance amount is grasped, it may be possible to inspect / analyze the state of the engine.

However, in the related art, as disclosed in Patent Document 1, "Method of Controlling Fuel Level by Cylinder in a Diesel Engine of a Common Rail Method" (Korean Patent Registration No. 10-0534724), the pilot injection fuel amount learning value is set separately for each cylinder. And determining whether the engine condition satisfies the main injection fuel amount learning condition, and if the learning condition is satisfied, determining whether the pilot injection fuel amount learning value for each cylinder is within the set first range; If there is a cylinder included in the first range, the process of calculating the main injection fuel amount by applying the main injection fuel amount correction ratio for the cylinder as a certain percentage of the pilot injection fuel amount learning value obtained from the cylinder, and not included in the first range If the cylinder exists, the process of determining whether the pilot injection fuel amount learning value of the cylinder is included in the set second range If there is a cylinder included in the second range, calculating the main injection fuel amount by applying the main injection fuel amount correction ratio for the cylinder as a predetermined percentage of the pilot injection fuel amount learning value obtained from the cylinder, and including the second range. If there is a cylinder that does not exist, the process of determining whether the pilot injection fuel amount learning value of the cylinder is included in the set third range, and if the cylinder included in the third range exists, the main injection fuel amount correction ratio for the cylinder is determined. Calculating the main injection fuel amount by applying a predetermined percentage of the pilot injection fuel amount learning value obtained in the step, and if there is a cylinder exceeding the third range, determining that the injector of the cylinder is old and outputting a failure message. Although there are many inventions related to the fuel amount control method as described above, Relating to the same invention or configuration testing / analysis of the state of the engine by using the deviation was the Browse difficult is the problem.

In addition, regarding the power / balance amount, as disclosed in Patent Document 2, "Method of Injector Defect Inspection of Diesel Engines" (Korean Patent Publication No. 10-2003-0091326), "Injector defect is measured by measuring the amount of power / balance." In the injector defect inspection method of the diesel engine for determining whether or not, the misfire caused by the fuel injection in the exhaust stroke is determined when the power / balance amount is measured ". Although there is an invention related to a method of inspecting a defect, there is a problem in that an invention related to a configuration of inspecting / analyzing the state of an engine using such a power / balance amount variation or deviation is difficult to find.

Patent Document 1: Republic of Korea Patent Registration No. 10-0534724 (2005.12.01.) Patent Document 2: Republic of Korea Patent Publication No. 10-2003-0091326 (2003.12.03.)

The present invention solves the problems of the existing invention described above, and the fuel injection amount signal distribution data having the characteristic that can be applied uniformly with a certain regularity even in a wide variety of engines varying characteristics such as the number of cylinders and displacement By simply analyzing and comparing the fuel injection amount of the vehicle to be measured with the fuel injection amount data of the new vehicle control group N and the faulty vehicle control group F, the engine status is efficiently checked according to the basic operating principles and characteristics of the vehicle engine. An object of the present invention is to provide an engine inspection analysis method and apparatus through fuel injection amount analysis of a compression ignition engine vehicle capable of diagnosing a condition.

In order to achieve the above object, the engine inspection analysis method through the fuel injection amount analysis of the compression ignition engine vehicle of the present invention, the fuel injection amount of each of the new vehicle control (N), the breakdown vehicle control (F) and the measurement target vehicle (T) A sensor signal input step (S1) for receiving a signal; and a new vehicle fuel injection amount measurement step (S2) of measuring distribution data of the fuel injection amount Sn of the new vehicle control N using the fuel injection amount signal; A fault difference fuel injection amount measurement step (S3) of measuring distribution data of the fuel injection amount Sf of the fault difference control group F using the fuel injection amount signal; and using the fuel injection amount signal, A target vehicle fuel injection amount measuring step (S4) of measuring distribution data of fuel injection amount (St) of the measurement target vehicle (T); and distribution data of the fuel injection amount (Sn) of the new vehicle control group (N) and the failure Primary control group (F An engine state analysis step S5 of comparing the distribution data of the fuel injection amount St of the measurement target vehicle with respect to the distribution data of the fuel injection amount Sf of An analysis result display step (S6) of displaying an engine state of the measurement target vehicle (T) analyzed through the state analysis step (S5); And a control unit.

In addition, the engine state analysis step (S5)

After calculating the average value An of the distribution data of the fuel injection amount Sn for each cylinder of the new vehicle control N, the maximum value Maxn and the minimum value Minn of the average value An for each cylinder were obtained. A new vehicle control variation calculation step (S10a) of selecting and obtaining a difference to obtain a new vehicle control variation range (Dn); and

After calculating the average value of the distribution data of the fuel injection amount (Sf) for each cylinder of the fault difference control group (F), select the maximum value and the minimum value of the mean value for each cylinder, and calculate the difference to find the difference between the fault difference control group (Df ) Calculates the fault difference control variation range (S10b) to obtain;

After obtaining the average value of the distribution data of the fuel injection amount (St) for each cylinder of the measurement target vehicle (T), select the maximum value and the minimum value of the average value for each cylinder, and obtain the difference to determine the difference between the measurement target vehicle (Dt Measurement target vehicle fluctuation range calculating step (S10c) for obtaining;

An engine state level value analysis unit that obtains an engine state level value EL1 satisfying the following expression (1) using the new vehicle control group variation width Dn, the failure difference control group variation width Df and the measurement subject vehicle variation width Dt Step SlOd; And a step of analyzing the state of fluctuation of the state (S10).

[Equation 1]

In this case, K is a predetermined correction coefficient.

In addition, the engine state analysis step (S5)

After deriving the minimum, maximum, standard deviation, and average values of the distribution data of the fuel injection amount Sn for each cylinder of the new vehicle control N, a new vehicle control normal distribution function derivation step of obtaining a new vehicle normal distribution function Fn ( S20a);

After calculating the minimum value, the maximum value, the standard deviation, and the average value of the distribution data of the fuel injection amount Sf for each cylinder of the fault difference control group F, the fault difference control normal distribution function for obtaining the fault difference normal distribution function Ff Derivation step (S20b);

After obtaining the minimum value, the maximum value, the standard deviation, and the average value of the distribution data of the fuel injection amount St for each cylinder of the measurement target vehicle T, the measurement target vehicle normal distribution for obtaining the measurement target vehicle normal distribution function Ft Function derivation step (S20c); and,

Deriving a new-vehicle distribution correcting function (Fcn) by multiplying the new-vehicle normal distribution function (Fn) by a new-vehicle variance correction coefficient (kn) based on an absolute value of the variance from the new-vehicle mean value; Wow,

Deriving a failure distribution correction function (Fcf) by multiplying the failure normal distribution function (Ff) by a failure difference variation correction coefficient (kf) based on the absolute value of the variance from the failure average value, Step S20e;

(Fct), which is obtained by multiplying the measurement target vehicle normal distribution function (Ft) by the measurement target vehicle variation correction coefficient (kt) based on the absolute value of the variance from the measurement target vehicle average value, A vehicle distribution correction function deriving step S20f;

The new vehicle distribution correction function Fcn, the fault difference distribution correction function Fcf, and the measurement target vehicle distribution correction function Fct are integrated with respect to each of the predetermined upper section Sh and lower section Sl. A distribution correction function integration step (S20g) for obtaining a new vehicle control engine speed change total amount Dev_n, a faulty vehicle control engine speed change total amount Dev_f and a measurement target vehicle engine speed change total amount Dev_t;

The engine state level value that satisfies Equation 2 using the new vehicle control engine speed change total amount (Dev_n), the faulty vehicle control engine speed change total amount (Dev_f) and the target vehicle engine speed change total amount (Dev_t). An engine state level value analysis step (S20h) of obtaining (EL2); And a normal distribution state analysis step (S20).

&Quot; (2) "

In addition, the engine state analysis step (S5)

After obtaining the minimum value, the maximum value, the standard deviation, and the average value of the distribution data of the fuel injection amount St for each cylinder of the measurement target vehicle T, the measurement target vehicle normal distribution for obtaining the measurement target vehicle normal distribution function Ft Function derivation step (S30a); and,

The difference between the frequency of occurrence Pt of each fuel injection amount of the distribution data of fuel injection amount St for each cylinder of the measurement target vehicle T and the value of the measurement target vehicle normal distribution function Ft for each fuel injection amount Section frequency calculation step (S30b) for calculating the frequency difference (PD) for each section; and,

A distribution section of the measurement target vehicle normal distribution function Ft is divided into a predetermined upper section Sh, an intermediate section Sm and a lower section Sl, and the upper section Sh and the lower section Sl, (PD) value of the interval is selected to select the selection frequency difference (PS). In the middle interval (Sm), only the case in which the frequency difference difference value (PD) A step S30c of frequency-difference discrimination for each interval selected by the frequency difference PS,

A correction screening frequency difference PDc obtained by multiplying the screening frequency difference PS by the measurement subject vehicle variation correction coefficient kt according to the absolute value of the variance from the average value of the measurement target vehicle normal distribution function Ft, A frequency difference calculation step S30d;

(Sd) based on the mean value as the center of the distribution range of the measurement target vehicle normal distribution function (Ft), and then the correction selection frequency difference PDc in the acceleration section (Sa) (Pd) obtained by integrating or integrating the correction selection frequency difference (PDc) in the deceleration section (Sd) obtained by integration or section-by-section addition and the deceleration frequency value (Pd) A step S30e of calculating a frequency value,

An engine state level value analyzing step (S30f) of obtaining an engine occupant level value (EL3) satisfying the following equation (3) using the acceleration frequency value (Pa) and the deceleration frequency value (Pd); And a normal distribution frequency difference analysis step (S30).

&Quot; (3) "

On the other hand, the engine inspection analysis device through the fuel injection amount analysis of the compression ignition engine vehicle according to an embodiment of the present invention,

The new vehicle control unit (N), the faulty vehicle control group (F) and the measurement target vehicle (N), which are connected to the sensor signal output unit 20 including the OBD-2 connector 10 of the vehicle, are required for the sensor signal input step S1. A sensor input / output connection unit 110 that receives each fuel injection amount signal of T);

A main control device (120) connected to the sensor input / output connection unit (110) to perform an engine inspection analysis method through fuel injection amount analysis of the compression ignition engine vehicle according to any one of claims 1 to 4;

A display unit 130 connected to the main control unit 120 for visually displaying an engine combustion state inspection analysis result and a result,

An operation input unit 140 connected to the main control unit 120 and receiving a user's operation input; And a control unit.

In addition, the fuel injection amount of the compression ignition engine vehicle is connected to the main control device 120 using any one or more of the wireless communication module 150 or the Internet network 160 connected to the main control device 120. External terminal device 170 that can query the performance results of the engine inspection analysis method through the analysis; And further comprising:

According to the present invention, by simply comparing and analyzing the fuel injection amount of the vehicle to be measured with the fuel injection amount data of the new vehicle control group (N) and the faulty vehicle control group (F), the engine can be efficiently operated according to the basic operating principle and characteristics of the vehicle engine. There is an advantage that the condition can be diagnosed by checking the condition of.

1: A graph showing torque change according to fuel injection amount in an ignition ignition engine vehicle.
2 is a view showing a screen of the measuring device showing the fuel injection amount deviation in the new vehicle control when the engine inspection analysis method through the fuel injection amount analysis of the compression ignition engine vehicle according to an embodiment of the present invention.
3 is a view showing a screen of a measuring device showing a fuel injection amount deviation in a vehicle of a general level when performing an engine inspection analysis method through fuel injection amount analysis of a compression ignition engine vehicle according to an embodiment of the present invention.
4 is a diagram showing a screen of a measuring device showing a fuel injection amount deviation in a control vehicle when the engine inspection analysis method through the fuel injection amount analysis of the compression ignition engine vehicle according to an embodiment of the present invention.
5 is a flowchart showing the overall flow of the engine inspection analysis method through the fuel injection amount analysis of the compression ignition engine vehicle according to an embodiment of the present invention.
6 is a flow showing a flow in the case of using the fluctuation condition analysis step (S10) as the engine condition analysis step (S5) of the engine inspection analysis method through the fuel injection amount analysis of the compression ignition engine vehicle according to an embodiment of the present invention chart.
7 is a flowchart illustrating a case where a normal distribution state analysis step S20 is used as an engine state analysis step S5 of an engine inspection analysis method through a fuel injection amount analysis of a compression ignition engine vehicle according to an embodiment of the present invention. Flowchart.
8 is a flow chart of the case of using a normal distribution frequency difference analysis step S30 as an engine condition analysis step S5 of an engine inspection analysis method through a fuel injection amount analysis of a compression ignition engine vehicle according to an embodiment of the present invention. Flowchart showing.
9 is a display screen when a normal distribution state analysis step S20 is used as an engine state analysis step S5 of an engine inspection analysis method through a fuel injection amount analysis of a compression ignition engine vehicle according to an embodiment of the present invention. Indicative drawing.
10: Display screen in the case of using the normal distribution frequency difference analysis step (S30) as the engine condition analysis step (S5) of the engine inspection analysis method through the fuel injection amount analysis of the compression ignition engine vehicle according to an embodiment of the present invention A diagram showing.
11 is a block diagram of an engine inspection analysis apparatus through fuel injection amount analysis of a compression ignition engine vehicle according to an embodiment of the present invention.

Hereinafter, with reference to the accompanying drawings, the engine inspection analysis method and apparatus through the fuel injection amount analysis of the compression ignition engine vehicle according to an embodiment of the present invention will be described in detail. First, it should be noted that, in the drawings, the same components or parts are denoted by the same reference numerals whenever possible. In describing the present invention, a detailed description of known functions and configurations incorporated herein will be omitted so as to avoid obscuring the subject matter of the present invention.

First, an engine inspection analysis method through fuel injection amount analysis of a compression ignition engine vehicle according to an embodiment of the present invention will be described.

Engine inspection analysis method through the fuel injection amount analysis of the compression ignition engine vehicle of the present invention is largely as shown in Figure 5, the sensor signal input step (S1), the new car fuel injection amount measurement step (S2), fault car fuel injection amount measurement step (S3), the target vehicle fuel injection amount measuring step S4, the engine state analysis step S5, and the analysis result display step S6.

First, the sensor signal input step S1 will be described. The sensor signal input step S1 is a step of receiving a sensor signal including a fuel injection amount signal of each of the new vehicle control group N, the faulty vehicle control group F, and the measurement target vehicle T as shown in FIG. 11. . In this case, the received sensor signals are similar to the ignition combustion engine in the case of a compression ignition engine such as a diesel engine, but the signals related to the ignition system are excluded and the sensor signals related to the control device for fuel injection are added. Information related to the driving state of each drive system related to engine control, such as vehicle running speed, engine coolant temperature signal, and operating state of vehicle and engine (hereinafter referred to as service data in the technical field related thereto). It is a step of receiving various service data including. In this case, the signals are standardized from the engine control unit (ECU) to the vehicle according to the OBD-2 standard through a controller area network (CAN) or a K-Line (OBD2 terminal: service data). It is a terminal to connect for receiving, and then it is transmitted through OBD2 terminal).

The On-Board Diagnosis-2 (OBD-2) is one of the regulations related to automobile exhaust gas in the United States. It is applied to a similar part in Korea. It is a computer embedded in a vehicle. (DTC) is stored and a warning light (MIL: Malfunction Indicator Light) is turned on when a hazardous exhaust gas is emitted beyond the reference level. And a method of expressing service data related thereto.

Existing OBD systems applied for the first time only check the electronic parts and the wiring, so it is not known that the exhaust gas increases due to deterioration of the catalyst or oxygen sensor, abnormal behavior of the sensor or actuator, etc. The standards of lighting and stored information of connectors, fault codes, and warning lights have not been standardized, so different vehicles and manufacturers need different connectors, and different data must be provided to interpret fault codes. It was.

In order to solve these problems, it is necessary to use the terminology and fault code of the communication connector, the communication specification electronic control part, the unit of the service data, and the display method of the communication device of general purpose diagnostic equipment as a standardized one. The OBD-2 regulation was amended by adding criteria and diagnostic requirements.

As the OBD-2 Act went into effect, the technical information related to the fault code and warning lamp lighting, which was diagnosed by the car manufacturer and designated by the car manufacturer, was only defined as OBD-1. If excessive discharge is over the standard, diagnose the failure of related parts or system and turn on the fault code and warning lamp in a standardized way. Technical contents related to service data display, etc. are defined as OBD-2. If the warning light turns on after 2 If there is not a malfunction and there is an excessive amount of exhaust gas, it is not difficult to operate the vehicle without repairing it. If the earth warning lamp is on, In case of no repair, OBD-3 is defined as a comprehensive technical content for compulsory improvement measures in case of excessive emissions such as restricting the operation of vehicles.

Diagnosis items in accordance with OBD-2 regulations include catalysts, engine burns, fuel gauges, coolant coolant leaks, evaporative gas leaks, oxygen sensors, EGR, Thermostat, PCV (Positive Crankcase Ventilation) valves and other engine or transmission controls. It includes all sensors and solenoids used for diagnosis, and does not additionally designate a specific name or range, but includes all factors that can cause emissions to exceed the standard.

The transmission of data according to OBD-2 regulations is done via CAN or K-Line using ISO9141-2 or KWP2000's vehicle fault diagnosis standard protocol. The ISO 9141-2 and KWP 2000 are standard protocols for vehicle failure diagnosis specified by ISO (International Organization for Standardization) and SAE (Society of Automotive Engineers).

The CAN (Controller Area Network) is a network communication method that can be used in a small range, and is a vehicle network system for providing digital serial communication between various measurement control equipment of a vehicle by a next generation vehicle diagnostic communication method. The CAN meets many kinds of real-time demands in the vehicle because it can reduce the weight and complexity, and transmit data at a very high speed by intelligently replacing the complicated electrical wiring and relay of the electronic components in the vehicle with serial communication lines. In addition, it can diagnose abnormality caused by electronic interference and communicate organically in case of accident during driving. As an ISO standard, it is applied to advanced automotive electronic systems and can integrate systems such as engine management, anti-lock braking systems (ABS), transmission management systems (TMS), air conditioning, door locks, and mirror adjustment. . The transmission speed of the CAN is 500Kbps ~ 1Mbps, which is more than 50 times faster than the existing communication speed, and most of them have recently applied this. On the other hand, K-Line is a vehicle diagnostic communication line named by the OBD regulations and has a speed of 10.4 Kbps.

 The present invention can also receive the service data from the ECU (ECU), the vehicle control computer at a very high speed through the CAN communication, it is possible to determine the state of the engine very quickly and the service data in a method other than CAN communication In case of receiving communication and CAN communication but slowing service data transmission to OBD2 terminal from Lee C.Yu, a computer embedded in the vehicle, it is more necessary to receive as many samples (number of received fuel injection values) in statistical analysis. The service data should be received for a long time.

Next, a new vehicle fuel injection amount measuring step S2 will be described. As shown in FIG. 5, in the new vehicle fuel injection amount measurement step S2, distribution data of the fuel injection amount Sn of the new vehicle control N is obtained by using the fuel injection amount signal measured in the new vehicle control N. It is a step of measuring. In this case, in order to measure the distribution data of the fuel injection amount Sn of the new vehicle control N, the fuel injection amount signal is repeatedly measured for a predetermined time in the new vehicle control N, and then stored in a database. After that, it is preferable to measure distribution data of the fuel injection amount Sn of the new vehicle control group N, and in general, it is also possible to use distribution data of a virtual vehicle having excellent condition as a standard of the new vehicle control group N.

Next, the fault-car fuel injection amount measuring step S3 will be described. As illustrated in FIG. 5, the fault difference fuel injection amount measuring step S3 is a step of measuring distribution data of the fuel injection amount Sf of the fault difference control group F using the fuel injection amount signal. In this case, in order to reproduce the state of the faulty vehicle for configuring the faulty vehicle control group F, experimentally, an operation such as removing a spark plug of one cylinder among the cylinders of the engine of the measurement target vehicle is performed. It is possible to reproduce the state of the faulty vehicle through operations such as making the operation difficult. In this case, too, in order to measure the distribution data of the fuel injection amount Sf of the fault difference control group F, the fuel injection amount signal is repeatedly measured for a predetermined time in the fault difference control group F, and then databased. After the storage, it is preferable to measure the distribution data of the fuel injection amount Sf of the fault difference control group F.

Next, the target vehicle fuel injection amount measurement step S4 will be described. The target vehicle fuel injection amount measuring step S4 is a step of measuring distribution data of the fuel injection amount St of the measurement target vehicle T to be analyzed using the fuel injection amount signal as shown in FIG. 5. . In this case, too, in order to measure the distribution data of the fuel injection amount St of the measurement target vehicle T, the fuel injection quantity signal is repeatedly measured for a predetermined time in the measurement target vehicle T, and is then databased. After the storage, the distribution data of the fuel injection amount St of the measurement target vehicle T is preferably measured.

On the other hand, the predetermined time interval for measuring the fuel injection amount signal in the new vehicle fuel injection amount measurement step (S2) to the target vehicle fuel injection amount measurement step (S4) is generally the respective fuel injection amount signal measurement values as a whole It is desirable to have a time interval that can accumulate as many as can form a statistically significant control or measurement group. Thus, for example, if the fuel injection quantity signal measurement is measured about 10 times a second, and about 1000 measurements are needed to form a statistically significant control, the predetermined time interval is about 100 seconds or more. It is preferable to make it. On the other hand, the predetermined time interval for measuring the fuel injection amount signal may be changed according to the number of measurement values required to form a statistically significant control with the period in which the fuel injection amount signal is measured. It is obvious to those who have a normal level of knowledge in this technical field.

Next, the engine condition analysis step S5 will be described. As shown in FIG. 5, the engine state analysis step S5 includes distribution data of the fuel injection amount Sn of the new vehicle control group N and distribution data of the fuel injection amount Sf of the breakdown vehicle control group F. And comparing and analyzing distribution data of the fuel injection amount St of the measurement target vehicle to determine an engine state of the measurement target vehicle T.

The engine state analysis step S5 may be configured in a wide variety of embodiments, and in one embodiment, the fluctuation state analysis step S10 and the normal distribution state analysis step as shown in FIGS. 6 to 8. S20) or the normal distribution frequency difference analysis step (S30) can be configured to include.

Hereinafter, the fluctuation state analysis step (S10), the normal distribution state analysis step (S20), or the normal distribution frequency difference analysis step (S30) will be described in detail.

First, the fluctuation state analysis step S10 will be described. The fluctuation state analysis step (S10) is a relatively simple statistical characteristics of the engine fuel injection amount distribution data of each of the new vehicle control (N) and the faulty vehicle control (F) and the engine fuel injection amount distribution of the measurement target vehicle (T) Comparing / analyzing the statistical characteristics of the data with each other to check / analyze the engine condition, as shown in FIG. 6, the new vehicle control variation calculation step (S10a), the breakdown vehicle control variation calculation step (S10b), and the measurement target vehicle variation It comprises a calculation step (S10c), the engine state level value analysis step (S10d).

In this case, the step of calculating the variation of the new vehicle control step (S10a) obtains an average value An of the distribution data of the fuel injection amount Sn for each cylinder of the new vehicle control group N, and then calculates the average value An of each cylinder. The maximum value (Maxn) and the minimum value (Minn) of the step to find the difference to obtain a new car control variation range (Dn).

In the step difference calculation step S10b of calculating a vehicle difference control step S10b, after calculating an average value of distribution data of the fuel injection amount Sf for each cylinder of the vehicle difference control group F, the maximum value and the minimum value of the average value for each cylinder are selected. The difference is obtained by calculating the difference between control faults (Df).

Next, the measurement target vehicle fluctuation calculation step (S10c), after calculating the average value of the distribution data of the fuel injection amount (St) for each cylinder of the measurement target vehicle (T), and the maximum value of the average value for each cylinder and In this step, the difference between the minimum values is selected and the difference of the vehicle to be measured (Dt) is obtained.

After performing the steps S10a to S10c of calculating the variation range of the new vehicle control group (S10a) to the calculation of the variation range of the vehicle-to-be-measured (S10c), the variation range Dn of the new vehicle control group, the variable- An engine state level value analysis step S10d for obtaining an engine state level value EL1 satisfying the following equation (1) is performed by using the engine state level value Dt to determine the engine state of the measurement subject vehicle T. [

In this case, K is a predetermined correction coefficient, and the engine state level value is represented by a value between 0 and 1, or between 0 and 100%.

The engine state of the measurement target vehicle T becomes closer to the new vehicle control N as the value shown through the fluctuation state analysis step S10 is closer to 0 and the correction coefficient K becomes 1 , It can be determined that the engine state of the measurement target vehicle T is closer to the failure control group F as the value shown through the variable width state analysis step S10 is closer to 1.

On the other hand, the fluctuation state analysis step (S10), the relatively simple statistical characteristics of each of the power / balance amount distribution data of each of the new vehicle control (N) and the breakdown vehicle control (F) and the measurement target of the vehicle (T) It is also possible to compare / analyze the statistical characteristics of the power / balance distribution data. In this case, in the sensor signal input step (S1), instead of receiving the respective fuel injection amount signals of the new vehicle control (N), the faulty vehicle control (F), and the measurement target vehicle (T), the new vehicle control (N), the faulty vehicle The power / balance signal of each of the control group F and the measurement target vehicle T is input.

Then, the fuel injection amount (Sn) for each cylinder of the new vehicle control group (N) in the new vehicle control range calculation step (S10a), the vehicle control group control range calculation step (S10b) and the measurement target vehicle variation range calculation step (S10c), respectively. Instead of obtaining distribution data of fuel injection amount Sf for each cylinder of the fault control group F, and distribution data of fuel injection amount St for each cylinder of the measurement target vehicle T, respectively, the new vehicle Power / balance amount distribution data for each cylinder of the control group N, power / balance amount distribution data for each cylinder of the fault difference control group F, and power / balance for each cylinder of the vehicle to be measured T After obtaining the balance amount distribution data, the average value is obtained for each distribution data, and then the maximum and minimum values of the average values for each cylinder are selected, and the difference is calculated to determine the difference between each variation range (Dn, Df, Dt). Obtained.

Next, an engine state level value analyzing step S10d for obtaining an engine state level value EL1 satisfying Equation 1 is performed to determine the engine state of the measurement target vehicle T. In other words, it is possible to determine the engine state of the measurement target vehicle T by performing the same process by performing the fluctuation range analysis step S10 but receiving a signal for power / balance amount instead of fuel injection amount.

Next, the normal distribution state analysis step S20 will be described. The normal distribution state analysis step (S20) is preferably applied when transmitting a fuel injection amount value from the engine control computer (ECU) irrespective of each cylinder of the engine, the new car control (N) and the faulty car Obtaining a normal distribution function of each engine fuel injection quantity distribution data of the control group F, and comparing / analyzing with the normal distribution function of the engine fuel injection quantity distribution data of the measurement target vehicle T to inspect / analyze the engine state As shown in FIG. 7, a new vehicle control normal distribution function derivation step (S20a), a fault difference control normal distribution function derivation step (S20b), a measurement target vehicle normal distribution function derivation step (S20c), and a new car distribution correction function derivation step (S20d), fault difference distribution correction function derivation step (S20e), measurement target vehicle distribution correction function derivation step (S20f), distribution correction function integration step (S20g) and engine state Is characterized in that comprises the reference, the analysis phase (S20h).

In this case, the new vehicle control normal distribution function deriving step (S20a), after obtaining the minimum value, the maximum value, the standard deviation and the average value of the distribution data of the fuel injection amount (Sn) for each cylinder of the new vehicle control (N), This step calculates the normal distribution function (Fn).

The normal distribution function is assumed to have a normal distribution when the variance X having an average m and a standard deviation σ has a probability density function f (x) given by the following equation (4).

This function is the most important statistical method as a function from the probability distribution of random errors obtained by measuring a quantity when the power is sufficiently large in the binomial distribution, and the logarithmic law is also explained from the nature of this function. In addition, this function is mainly used for sampling survey.

Next, the step difference control normal distribution function derivation step (S20b), after obtaining the minimum value, the maximum value, the standard deviation and the mean value of the distribution data of the fuel injection amount (Sf) for each cylinder of the fault difference control (F), In this step, the error difference normal distribution function Ff is obtained.

Next, the measurement target vehicle normal distribution function derivation step (S20c), after obtaining the minimum value, the maximum value, the standard deviation and the average value of the distribution data of the fuel injection amount (St) for each cylinder of the measurement target vehicle (T), In this step, the measurement target vehicle normal distribution function Ft is obtained.

Each of the normal distribution functions derived through the new vehicle control normal distribution function derivation step (S20a) to the measurement target vehicle normal distribution function derivation step (S20c) is shown in FIG. 9 on a graph of varying the fuel injection amount of the engine. It will have the same shape as That is, the new-order normal distribution function Fn represented by a dotted line in FIG. 9 has a shape having a high probability and relatively narrow distribution near the mean value (center value), and a fault-difference normal distribution function represented by a dashed-dotted line in FIG. 9. (Ff) has a low probability and relatively wide distribution near the mean value (center value), and the measurement target vehicle normal distribution function Ft represented by the solid line in FIG. 9 is equal to the new vehicle normal distribution function Fn. It has a characteristic that is located between the fault difference normal distribution function (Ff). Therefore, qualitatively, as the shape of the measurement target vehicle normal distribution function Ft approaches the shape of the new-model normal distribution function Fn, the engine state can be judged to be in a good state (state close to the new vehicle) As the shape of the measurement target vehicle normal distribution function Ft approaches the shape of the failure normal distribution function Ff, the engine state can be determined to be in a poor state (a state close to the failure).

9 illustrates an example in which the average values of the new vehicle normal distribution function Fn, the fault difference normal distribution function Ff, and the measurement target vehicle normal distribution function Ft coincide with each other. According to the measured values, graphs of the new vehicle normal distribution function (Fn), the fault difference normal distribution function (Ff), and the measurement target vehicle normal distribution function (Ft) are formed by moving left and right on the x-axis engine fuel injection amount (s) axis, respectively. Can be. In this case, the case where the average value is different in the measurement target vehicle normal distribution function and shifts on the x-axis is considered when analyzing the engine taming level through Equation 3 above. That is, in order to analyze how much the overall level of the engine of the measurement target vehicle (T) falls between the new vehicle (N) and the faulty vehicle (F), the measurement target vehicle normal distribution function (Ft) and the new vehicle normal distribution function (Fn ), The mean value of the fault difference normal distribution function (Ff) is made equal.

Meanwhile, each of the normal distribution functions derived through the new vehicle control normal distribution function derivation step (S20a) to the measurement target vehicle normal distribution function derivation step (S20c) has a probability in a predetermined engine fuel injection amount distribution value section. In order to understand the distribution degree and the change amount of the engine fuel injection amount, the actual engine rotation is caused by the change amount (or distribution amount) of the engine rotation time in addition to the probability of the predetermined engine fuel injection amount distribution value range in the engine fuel injection amount distribution data. Converting to a function that can represent a change in number is required. That is, when the new vehicle normal distribution function Fn, the fault difference normal distribution function Ff, and the measurement target vehicle normal distribution function Ft are integrated in a predetermined fuel injection amount distribution value section, the value obtained is simply the predetermined fuel injection amount. It is only a value indicating the probability that the fuel injection amount is distributed in the distribution value section. Therefore, the integral values of the new vehicle normal distribution function Fn, the fault difference vehicle normal distribution function Ff, and the measurement target vehicle normal distribution function Ft are all 1, i.

For this conversion, the new vehicle normal distribution function Fn, the failure normalization distribution function Ff and the measurement target vehicle normal distribution function Ft are derived from a new vehicle distribution correction function deriving step S20d, Step S20e and the measurement subject vehicle distribution correction function deriving step S20f.

Here, the correction function is a function corrected using a conversion coefficient for converting a fuel injection amount change into an engine speed change amount, and when the conversion factor is multiplied by a normal distribution function in the predetermined fuel injection amount distribution value section. The integrated value is the total amount of the change amount of the engine speed in the predetermined fuel injection amount distribution value section.

The value of this conversion coefficient differs depending on the type of engine, such as the compression ratio, the displacement, the number of cylinders, and the air / fuel ratio, the engine speed, etc. However, it should be noted that this difference is not a problem in the present invention at all.

First, when the entire section of the fuel injection distribution is divided into several arbitrary stages, and when viewed in each of the sections, the present invention provides the same type of vehicle as in the case of a new car (N), a faulty car (F), and a target car (T). Since the same engine is being analyzed, the correction function values are the same. Of course, there may be a difference in the rotational speed change with respect to the fuel injection amount change depending on the aging, but it is not practical to consider such factors due to aging, and the correction coefficient used in the electronic control makers in the technical field of the present invention is usually a new car. Use as one standard. Therefore, when the correction function is substituted into Equation (2), denominator molecules are all substituted equally and can be deleted, so that they are not related to the magnitude of the value.

Second, in the case of the entire fuel injection distribution, the conversion coefficient is changed to each fuel injection variation when integrating the new vehicle normal distribution function (Fn), the fault difference normal distribution function (Ff), and the measured vehicle normal distribution function (Ft). Integrating after multiplying results in a large change in the fuel injection quantity change, which results in a large integration value. In other words, if you integrate the normal distribution function for all fuel injection distributions without multiplying the fuel injection value by the correction function, you will get 1 (100%) as a simple probability, but if the fuel injection value is integrated by multiplying the conversion factor, the engine The greater the amount of change in fuel injection amount, the greater the integral value becomes.

As a result, the error of the correction function value causes an error in the total amount of engine speed change of the new car (N), the fault car (F), and the target car (T), but the new car (N), the fault car (F), and the target car ( It can be seen that there is no difference in the relative ratio of each engine speed change amount of T). Therefore, the value of the conversion coefficient experimentally changes the fuel injection amount 1 mCC for all the cylinders at idle under no load conditions, so that the engine speed change is 100-300 rpm. When the value is received as one value, it is used as it is, and when receiving the fuel injection amount value for each cylinder, it is preferable to use the value obtained by dividing the intermediate value 90 by the number of cylinders.

However, when the fuel injection amount is changed from the average value on the x-axis as shown in FIG. 9, it causes an engine speed change, and in real engines, noise increases with vibration, and it is undesirable in terms of quietness such as shaking the engine and the body. It shows various unpleasant phenomena.

In consideration of this, in the present invention, it is preferable to divide the fuel injection amount change, that is, the x-axis in 5 steps away from the average value in FIG. In other words, the level where vibration is hardly seen in one step (0-0.3 mCC as the amount of fuel injection change) is called the normal range, and the value of the correction function is close to zero, and the vibration occurs in two steps, but it is not concerned. (0.4-0.6mCC in the amount of change in fuel injection), the noise car body vibrations occur along with the vibration in three stages, and the degree of anxiety (0.7-0.9mCC in the fuel injection range) is severe. Degree of unpleasant feeling (1.0-1.2mCC in fuel injection change), and the last 5 stages show the fear that the engine may be overwhelmed due to severe vibration and engine shake (1.2mCC or more in fuel injection change) It is also realistically possible to add additional corrections as the first step is closer to zero and the closer to five steps is closer to one.

For reference, the reason why the average values of the new vehicle normal distribution function (Fn), the fault difference normal distribution function (Ff) and the measurement target vehicle normal distribution function (Ft) are equal to each other is the same. The change in fuel injection amount applied is the difference between the actual fuel injection value and the average value.

The new vehicle distribution correction function deriving step (S20d) includes a new car distribution correction function (Fcn) multiplied by the new car normal distribution function (Fn) multiplied by the new car variance correction coefficient (kn) by the absolute value of the variance from the new car average value. It's a step. In this case, the new vehicle variance correction coefficient kn can be set experimentally or theoretically, and it is possible to linearly change the absolute value of the variance from the new-vehicle average value in the section to which the new- It is common to be given a proportional value. That is, in FIG. 9, the new vehicle distribution correction function Fcn in the predetermined fuel injection amount section (position) is the predetermined fuel injection amount section (from the central axis (symmetry axis) of the new car normal distribution function Fn representing the new car average value). It is possible to set to a value proportional to the absolute value of the variable amount up to the position (that is, the absolute value of the distance from the central axis (symmetry axis) of the new vehicle normal distribution function Fn to the predetermined fuel injection amount section (position)). Do. In this case, the same correction function is applied to the new vehicle normal distribution function (Fn), the fault difference normal distribution function (Ff), and the measurement target vehicle normal distribution function (Ft) as described for the value of the correction function. In the case where the amount of change in the injection amount increases, that is, in FIG. 9, the x-axis may be divided into a plurality of stages away from the average value to give an additional correction factor value that may be weighted in consideration of the phenomenon of the engine appearing in each section.

Next, the failure distribution correcting function derivation step (S20e) derives the failure distribution normalization function (Ff) by multiplying the failure difference variation correction coefficient (kf) by the absolute value of the variance from the failure average value And obtaining a distribution correction function Fcf. In this case, it is also possible to experimentally or theoretically set the error correction coefficient kf, and it is also possible to set the error correction coefficient kf to the absolute value of the variance from the error difference average value It is generally given as linearly proportional values. In this case, the same correction function is applied to the new vehicle normal distribution function (Fn), the fault difference normal distribution function (Ff) and the measurement target vehicle normal distribution function (Ft) as described for the value of the correction function. In the case where the fuel injection amount is increased, that is, in FIG. 9, the x-axis may be divided into a plurality of stages away from the average value to give an additional correction factor value that may be weighted in consideration of the phenomenon of the engine appearing in each section. .

Next, the measurement target vehicle distribution correcting function deriving step S20f is a step of deriving a measurement target vehicle distribution correction function (kt (k)) based on the absolute value of the variance from the measurement target vehicle average value with respect to the measurement target vehicle normal distribution function ) To obtain a measurement target vehicle distribution correcting function Fct. In this case also, the measurement target vehicle variation correction coefficient kt can be set experimentally or theoretically, and in the section to which the measurement target vehicle variation correction coefficient kt is to be applied, the variation from the measurement target vehicle average value And is generally given as a value that is linearly proportional to the absolute value of? In this case, the same correction function is applied to the new vehicle normal distribution function (Fn), the fault difference normal distribution function (Ff), and the measurement target vehicle normal distribution function (Ft) as described for the value of the correction function. In the case where the amount of change in the injection amount increases, that is, in FIG. 9, the x-axis may be divided into a plurality of stages away from the average value to give an additional correction factor value that may be weighted in consideration of the phenomenon of the engine appearing in each section.

Next, the distribution correction function integration step S20g will be described. As shown in FIG. 7, the normal distribution function integration step S20g is performed with respect to the new vehicle distribution correction function Fcn, the fault difference distribution correction function Fcf, and the measurement target vehicle distribution correction function Fct. Engine rotation in a region where speed of engine rotation is accelerated (hereinafter referred to as an upper section) (Sh) and a region in which fuel injection quantity change is smaller than an average value, as shown in FIG. The new vehicle control engine speed change amount (Dev_n) integrated by multiplying the new vehicle control normal distribution function (Fn) by the new vehicle control variable correction coefficient (kn) by integrating with respect to the section for slowing down (hereinafter, referred to as a lower section) (Sl). The total vehicle engine speed change (Dev_f) and the vehicle to be measured are integrated by multiplying the vehicle control control normal distribution function (Ff) by the vehicle control group variable correction coefficient (kf). Figures distribution function multiplied by the number of measurement target difference variance correction coefficient (kt) a measurement target engine speed difference integral to (Ft) is a step of obtaining the total amount of change (Dev_t).

In this case, integrating with respect to the upper section Sh and the lower section Sl is to obtain a total amount of engine speed change and make a relative comparison so that the measurement target vehicle T is between the new vehicle N and the faulty vehicle F. It is to analyze how much level is shown in. At this time, if the fuel injection quantity change in the upper section is large, the engine is rotating slower than normal, and the engine speed is increased to increase the engine injection power by increasing the fuel injection amount. It indicates that it is rotating, which reduces fuel injection and thus reduces engine torque and compensates for slower rotation. When the amount of change in fuel injection in the upper section Sh and the lower section Sl is large, that is, as the distance from the center of the x-axis increases, the engine rotation speed is increased and the phenomenon felt by the engine is changed. Depending on the degree, it is possible to divide the upper section Sh and the lower section Sl into several sections experimentally or theoretically, and generally, δ (standard deviation) at which the inflection point is located from the central axis of the normal distribution function. It is possible to set intervals spaced apart as much as the upper interval Sh and the lower interval Sl, respectively.

Next, the engine state level value analysis step S20h will be described. The engine state level analysis step (S20h) is, as shown in Figure 7, the new vehicle control engine speed change total amount (Dev_n), the trouble car control engine speed change total amount (Dev_f) and the target vehicle engine speed change total amount By using Dev_t, the engine state level value EL2 satisfying Equation 2 below is obtained.

In this case, the closer the engine state level value EL2 is to 0, the closer the state of the measurement target vehicle T is to the new vehicle control N. If the engine state level value EL2 is 1 It can be determined that the engine state of the measurement target vehicle T is closer to the failure control group F as the distance is closer.

Next, the normal distribution frequency difference analysis step S30 will be described. The normal distribution frequency difference analysis step (S30) is even more precisely deviated from the normal distribution of the distribution characteristics of the fuel injection amount of the measurement target vehicle (T) (whether the fuel injection amount is biased toward the increase or decrease) In order to grasp, as shown in Fig. 8, the measurement target vehicle normal distribution function derivation step (S30a), section frequency difference calculation step (S30b), section frequency difference selection step (S30c), correction selection frequency It is characterized in that it comprises a difference calculation step (S30d), the frequency value calculation step (S30e) and the engine state level value analysis step (S30f).

First, the measurement target vehicle normal distribution function deriving step S30a will be described. The measurement target vehicle normal distribution function deriving step (S30a), after obtaining the minimum value, the maximum value, the standard deviation and the average value of the distribution data of the fuel injection amount (St) for each cylinder of the measurement target vehicle (T), the measurement target The vehicle normal distribution function Ft is obtained.

Next, the step of calculating the frequency difference for each section (S30b) is the actual occurrence frequency (Pt) of each fuel injection amount and the fuel injection amount of each fuel injection amount of the distribution data of the fuel injection amount (St) for each cylinder of the measurement target vehicle (T) A step of calculating a frequency difference (PD) for each section, which is a difference from a value calculated by integrating a measurement target vehicle normal distribution function (Ft). That is, in FIG. 10, the frequency difference PD for each section, which is a difference between the graph indicating the measurement target vehicle normal distribution function Ft and the bar graph indicating the occurrence frequency Pt for each fuel injection amount, is calculated.

In this case, the bar graph is the frequency of occurrence of the change in fuel injection amount, which is the actual occurrence frequency indicating how many times the value corresponding to each section of the x-axis of FIG. The value calculated from the normal distribution function (Ft) is the value obtained by integrating the normal distribution function (Ft) with respect to the x-axis section of FIG. 10 by multiplying the total number of fuel injection signal received. . Since this is a basic content widely known in the statistical mathematics related to the present invention, a detailed description thereof will be omitted.

Next, in the frequency difference selection step for each section (S30c) by dividing the distribution section of the measurement target vehicle normal distribution function (Ft) into a predetermined upper section (Sh), intermediate section (Sm) and lower section (Sl), In the upper section Sh and the lower section Sl, when the frequency difference PD value for each section is positive (that is, the occurrence frequency Pt for each fuel injection amount is the measurement target vehicle normal distribution function for each fuel injection amount) If only greater than the (Ft) value is selected and selected as the screening frequency difference (PS), and in the intermediate section (Sm) when the frequency difference (PD) value for each section is negative (that is, generated for each fuel injection amount) Selecting only the frequency frequency PS when the frequency Pt is generated smaller than the measured vehicle normal distribution function Ft value for each fuel injection amount. The reason for selecting the frequency difference PD for each section in the upper section Sh and the lower section Sl and the middle section Sm by discriminating the positive and negative values, respectively, is the upper section Sh. ) And the lower interval Sl is a state in which the value of the frequency difference PD for each section approaches a fuel injection quantity distribution in the case of a faulty vehicle, and the actual engine state of the measurement target vehicle T This is because the degree of deviation (that is, the degree of aging or abnormality) from the measured vehicle normal distribution function Ft obtained by the statistical method is better represented. Similarly, when the frequency difference PD for each section in the intermediate section Sm is negative, the actual engine of the measurement target vehicle T is in a state of approaching the fuel injection amount distribution in the case of a fault car. The state better represents the degree of deviation from the measured vehicle normal distribution function Ft obtained by the statistical method (that is, the degree of aging or abnormality). Here, it should be noted that the graph of the measurement target vehicle normal distribution function (Ft) means a standard of tendency that the measurement target vehicle universally shows.

Meanwhile, the method of distinguishing and determining the upper section Sh, the lower section Sl, and the intermediate section Sm may be variously experimentally or theoretically. In an embodiment of the present invention, The upper section Sh and the lower section Sl are set as the middle section Sm and the other sections as the upper section Sh and the lower section Sl, respectively, between the sections spaced apart from the center axis of the distribution function by δ (standard deviation) It is possible.

In the present invention, according to the amount of change in fuel injection amount divided by the degree of phenomenon that is actually felt in the engine, the background is as follows. That is, the amount of change in fuel injection amount away from the average value of the x-axis of FIG. 11 is determined as the intermediate section sm, which can be referred to as a normal range, in which vibration is hardly exhibited in one step (about 0-0.3 mCC as the amount of fuel injection change). The second stage is the range where vibration occurs, but it is not worried about it (0.4-0.6mCC as the variation of fuel injection amount), and the third stage is the range where the noise of the vehicle body vibration occurs along with the vibration (the fuel injection range) 0.7-0.9mCC), the 4th stage is severe in the 3rd stage and the degree of unpleasant feeling (1.0-1.2mCC as the fuel injection change amount), and the last 5th stage causes the engine shaking with severe vibration It is divided into the degree of concern (1.2mCC or more in the fuel injection amount change) as if there is a large crowd, and if the change amount is positive (+), the upper section (Sh) is negative. It was defined as the interval (Sl). These steps are quantitative classification that can be divided through the qualitative division divided according to the degree of reaction felt through the engine phenomenon and the scale (RPM gauge variation) that can be seen in the driver's seat gauge as in the present invention. It is possible to divide into.

Next, the correction selection frequency difference calculating step S30d calculates the correction target value Kt based on the absolute value of the variation from the average value of the measurement target vehicle normal distribution function Ft to the selection frequency difference PS, To obtain the correction selection frequency difference PDc. In this case, the measurement target vehicle variance correction coefficient kt may be set experimentally or theoretically, and the absolute value of the variance from the average value of the measurement target vehicle in the section to which the measurement target vehicle variance correction coefficient kt is to be applied. It is usually given as a value that is linearly proportional to the value. In this case, as described in the correction function Ft applied to Equation 2, it is also possible to use the same value for the new car N, the fault car F, and the measurement target car T.

Next, the frequency value calculation step S30e divides the distribution interval of the measurement target vehicle normal distribution function Ft into an acceleration interval Sa and a deceleration interval Sd with an average value as a center, ) And the correction selection frequency difference (PDc) in the deceleration section (Sd) by integrating or section-by-section summing up the correction selection frequency difference (PDc) And a deceleration frequency value (Pd) obtained through the step of FIG. In this case, the acceleration section Sa and the deceleration section Sd are divided based on the average value of the measurement target vehicle normal distribution function Ft as a center axis, as shown in FIG. 10.

Next, by using the acceleration frequency value Pa and the deceleration frequency value Pd through the engine state level value analysis step S30f, the engine occupant level value EL3 that satisfies the following expression (3) is obtained .

In this case, the sign of the engine taming level value EL3 indicates whether the actual engine state of the measurement subject vehicle T is mainly operated in the direction of increasing the engine speed (when the engine taming level value EL3 is positive Or if the actual engine state of the to-be-measured vehicle T is mainly operated in the direction of reducing the engine speed (when the engine running level value EL3 is negative).

The magnitude of the engine starting level value EL3 indicates the degree to which the actual engine state of the measurement subject vehicle T is biased in the direction of increasing or decreasing the engine speed.

Finally, the analysis result display step S6 will be described.

The analysis result display step S6 is a step of displaying the engine state of the measurement target vehicle T analyzed through the engine state analysis step S5 as shown in FIG. 5.

In this case, the analysis result display step (S6) in the fluctuation range analysis step (S10), the normal distribution state analysis step (S20) or the normal distribution frequency difference analysis step (S30) constituting the engine state analysis step (S5). In addition to displaying the engine state level value EL1, the engine state level value EL2, and the engine taming level value EL3, respectively, as shown in FIG. 9 or FIG. 10, the new car normal distribution function Fn, It is preferable to display a variety of information such as a fault difference normal distribution function Ff, a measurement target vehicle normal distribution function Ft, a frequency of occurrence Pt for each fuel injection amount, and a screening frequency difference PS.

Hereinafter, an engine inspection analysis apparatus 100 through fuel injection amount analysis of a compression ignition engine vehicle according to an embodiment of the present invention will be described. As shown in FIG. 11, the engine inspection and analyzing apparatus 100 includes a sensor input / output connection unit 110, a main control unit 120, a display unit 130, and an operation input unit 140. It is done.

First, the sensor input / output connection unit 110 will be described. As illustrated in FIG. 11, the sensor input / output connection unit 110 includes an OBD-2 connector of a vehicle installed in each vehicle of the new vehicle control N, the faulty vehicle control F, and the measurement target vehicle T ( It is connected to each of the sensor signal output unit 20 including a) has a function to receive the respective fuel injection amount signal required for the sensor signal input step (S1). On the other hand, when the present invention is implemented using the power / balance amount, the sensor input and output connection unit 110 is applied to each vehicle of the new vehicle control (N), the faulty vehicle control (F) and the measurement target vehicle (T). It is also connected to the sensor signal output unit 20 including the OBD-2 connector 10 of the installed vehicle, respectively, and has a function of receiving the respective power / balance amount signals required for the sensor signal input step S1. It is preferable.

Next, the main control device 120 will be described. As shown in FIG. 11, the main control device 120 is connected to the sensor input / output connection unit 110 and has a function of performing an engine inspection analysis method through the fuel injection amount analysis of the compression ignition engine vehicle. The technique of configuring and programming the main control apparatus 120 to have a function of performing an engine inspection analysis method through the fuel injection amount analysis of the compression ignition engine vehicle is a technique widely known and practiced in the technical field to which the present invention belongs. As it is level, detailed description is omitted.

Next, the display unit 130 will be described. As illustrated in FIG. 11, the display unit 130 is connected to the main control device 120 and has a function of visually displaying an engine combustion state inspection analysis process and results.

Next, the operation input unit 140 will be described. As illustrated in FIG. 11, the manipulation inputter 140 is connected to the main control apparatus 120 and has a function of receiving a manipulation input of a user. The operation input unit 140 may include any one or more of various input means such as a keyboard, a keypad, a mouse, and a tablet.

On the other hand, the engine inspection analysis device 100 through the fuel injection amount analysis of the compression ignition engine vehicle of the present invention, as shown in Figure 11, the wireless communication module 150 or the Internet network connected to the main control device 120 An external terminal device 170 connected to the main control device 120 using any one or more of the 160 and inquiring the result of performing the engine inspection analysis method through the fuel injection amount analysis of the compression ignition engine vehicle. It is preferably configured to further include. In this case, the external terminal 170 may include any one or more of various devices such as a PDA, a smart phone, a tablet PC, and a notebook computer.

Optimal embodiments have been disclosed in the drawings and specification. Although specific terms have been employed herein, they are used for purposes of illustration only and are not intended to limit the scope of the invention as defined in the claims or the claims. Therefore, those skilled in the art will appreciate that various modifications and equivalent embodiments are possible without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

N: New vehicle control group F: Failure control group
T: Target vehicle
10: OBD-2 connector 20: Sensor signal output section
100: engine inspection analysis device through fuel injection amount analysis of compression ignition engine vehicle
110: Sensor I / O connection
120: Main control device
121: main control unit 122:
123: nonvolatile memory 124: volatile memory
130: display section 140: operation input section
150: wireless communication module 160: internet network
170: External terminal

Claims (6)

delete A sensor signal input step S1 of receiving sensor signals including fuel injection quantity signals of each of the new car control N, the breakdown car control F, and the measurement target vehicle T;
A new vehicle fuel injection amount measuring step (S2) of measuring distribution data of fuel injection amount Sn of the new vehicle control group N using the fuel injection amount signal;
A fault difference fuel injection amount measuring step (S3) of measuring distribution data of the fuel injection amount (Sf) of the fault difference control group (F) using the fuel injection amount signal;
A measurement target vehicle fuel injection amount measurement step (S4) of measuring distribution data of the fuel injection amount St of the measurement target vehicle T to be analyzed using the fuel injection amount signal;
The distribution data of the fuel injection amount St of the measurement target vehicle is compared with the distribution data of the fuel injection amount Sn of the new vehicle control group N and the distribution data of the fuel injection amount Sf of the breakdown vehicle control group F. An engine state analysis step S5 of analyzing and determining an engine state of the measurement target vehicle T;
An analysis result display step (S6) of displaying an engine state of the measurement subject vehicle (T) analyzed through the state analysis step (S5); Characterized in that comprises a,
The engine condition analysis step (S5)
After calculating the average value An of the distribution data of the fuel injection amount Sn for each cylinder of the new vehicle control N, the maximum value Maxn and the minimum value Minn of the average value An for each cylinder were obtained. Selecting a new car control variation range (Dn) to obtain a difference and calculating a difference (Sn);
After calculating the average value of the distribution data of the fuel injection amount (Sf) for each cylinder of the fault difference control group (F), select the maximum value and the minimum value of the mean value for each cylinder, and calculate the difference to find the difference between the fault difference control group (Df Calculating a fault difference control variation range (S10b);
After calculating the average value of the distribution data of the fuel injection amount (St) for each cylinder of the measurement target vehicle (T), select the maximum value and the minimum value of the average value for each cylinder, and calculate the difference to determine the difference between the measurement target vehicle (Dt A measurement target vehicle variation width calculating step (S10c) for obtaining);
An engine state level value analysis unit that obtains an engine state level value EL1 satisfying the following expression (1) using the new vehicle control group variation width Dn, the failure difference control group variation width Df and the measurement subject vehicle variation width Dt Step SlOd; Engine inspection analysis method through the fuel injection amount analysis of the compression ignition engine vehicle, characterized in that it comprises a fluctuation range analysis step (S10) comprising a.

[Equation 1]

In this case, K is a predetermined correction coefficient.
A sensor signal input step S1 of receiving sensor signals including fuel injection quantity signals of each of the new car control N, the breakdown car control F, and the measurement target vehicle T;
A new vehicle fuel injection amount measuring step (S2) of measuring distribution data of fuel injection amount Sn of the new vehicle control group N using the fuel injection amount signal;
A fault difference fuel injection amount measuring step (S3) of measuring distribution data of the fuel injection amount (Sf) of the fault difference control group (F) using the fuel injection amount signal;
A measurement target vehicle fuel injection amount measurement step (S4) of measuring distribution data of the fuel injection amount St of the measurement target vehicle T to be analyzed using the fuel injection amount signal;
The distribution data of the fuel injection amount St of the measurement target vehicle is compared with the distribution data of the fuel injection amount Sn of the new vehicle control group N and the distribution data of the fuel injection amount Sf of the breakdown vehicle control group F. An engine state analysis step S5 of analyzing and determining an engine state of the measurement target vehicle T;
An analysis result display step (S6) of displaying an engine state of the measurement subject vehicle (T) analyzed through the state analysis step (S5); Characterized in that comprises a,
The engine condition analysis step (S5)
After deriving the minimum, maximum, standard deviation, and average values of the distribution data of the fuel injection amount Sn for each cylinder of the new vehicle control N, a new vehicle control normal distribution function derivation step of obtaining a new vehicle normal distribution function Fn ( S20a);
After calculating the minimum value, the maximum value, the standard deviation, and the average value of the distribution data of the fuel injection amount Sf for each cylinder of the fault difference control group F, the fault difference control normal distribution function for obtaining the fault difference normal distribution function Ff Derivation step (S20b);
After obtaining the minimum value, the maximum value, the standard deviation, and the average value of the distribution data of the fuel injection amount St for each cylinder of the measurement target vehicle T, the measurement target vehicle normal distribution for obtaining the measurement target vehicle normal distribution function Ft A function derivation step S20c;
A new vehicle distribution correction function deriving step (S20d) for obtaining a new vehicle distribution correction function (Fcn) multiplied by the new vehicle variable correction coefficient (kn) by the absolute value of the variance from the new vehicle average value with respect to the new vehicle normal distribution function (Fn);
Deriving a fault difference distribution correction function for obtaining a fault difference distribution correction function Fcf from the fault difference normal distribution function Ff multiplied by a fault difference variance correction coefficient kf by the absolute value of the variance from the fault difference average value Step S20e;
A measurement for obtaining a measurement target vehicle distribution correction function Fct with respect to the measurement target vehicle normal distribution function Ft, which is multiplied by the measurement target vehicle variance correction coefficient kt by the absolute value of the variance from the measurement target vehicle average value. A target vehicle distribution correction function deriving step (S20f);
With respect to the new vehicle distribution correction function Fcn, the fault difference distribution correction function Fcf, and the measurement target vehicle distribution correction function Fct, an integral is obtained for each predetermined upper section Sh and lower section Sl. A distribution correction function integration step (S20g) for obtaining a new vehicle control engine speed change total amount Dev_n, a faulty vehicle control engine speed change total amount Dev_f and a measurement target vehicle engine speed change total amount Dev_t;
The engine state level value that satisfies Equation 2 using the new vehicle control engine speed change total amount (Dev_n), the faulty vehicle control engine speed change total amount (Dev_f) and the target vehicle engine speed change total amount (Dev_t). An engine state level value analysis step (S20h) of obtaining (EL2); Engine inspection analysis method through the fuel injection amount analysis of the compression ignition engine vehicle, characterized in that comprises a normal distribution state analysis step (S20) comprising a.

&Quot; (2) "

The method of claim 3,
The engine condition analysis step (S5)
After obtaining the minimum value, the maximum value, the standard deviation, and the average value of the distribution data of the fuel injection amount St for each cylinder of the measurement target vehicle T, the measurement target vehicle normal distribution for obtaining the measurement target vehicle normal distribution function Ft A function derivation step S30a;
By integrating the actual occurrence frequency Pt of each fuel injection amount of the distribution data of fuel injection amount St for each cylinder of the measurement target vehicle T and the measurement target vehicle normal distribution function Ft for each fuel injection amount A step-by-step frequency difference calculation step (S30b) of calculating a step-by-step frequency difference (PD) which is a difference from a value obtained by multiplying the calculated value by the total number of data of the fuel injection amount signal actually generated;
A distribution section of the measurement target vehicle normal distribution function Ft is divided into a predetermined upper section Sh, an intermediate section Sm and a lower section Sl, and the upper section Sh and the lower section Sl, (PD) value of the interval is selected to select the selection frequency difference (PS). In the middle interval (Sm), only the case in which the frequency difference difference value (PD) Frequency-difference discrimination step S30c for each interval to select the frequency difference PS;
A correction screening frequency difference PDc obtained by multiplying the screening frequency difference PS by the measurement subject vehicle variation correction coefficient kt according to the absolute value of the variance from the average value of the measurement target vehicle normal distribution function Ft, Frequency difference calculation step S30d;
(Sd) based on the mean value as the center of the distribution range of the measurement target vehicle normal distribution function (Ft), and then the correction selection frequency difference PDc in the acceleration section (Sa) (Pd) obtained by integrating or integrating the correction selection frequency difference (PDc) in the deceleration section (Sd) obtained by integration or section-by-section addition and the deceleration frequency value (Pd) A frequency value calculating step (S30e) to obtain the frequency value;
An engine state level value analyzing step (S30f) of obtaining an engine occupant level value (EL3) satisfying the following equation (3) using the acceleration frequency value (Pa) and the deceleration frequency value (Pd); The engine inspection analysis method through the fuel injection amount analysis of the compression ignition engine vehicle, characterized in that comprises a normal distribution frequency difference analysis step (S30) comprising a.

&Quot; (3) "

In the engine inspection analysis apparatus through the fuel injection amount analysis of the compression ignition engine vehicle performing the engine inspection analysis method by the fuel injection amount analysis of the compression ignition engine vehicle of any one of claims 2 to 4,

The new vehicle control unit (N), the faulty vehicle control group (F) and the measurement target vehicle (N), which are connected to the sensor signal output unit 20 including the OBD-2 connector 10 of the vehicle, are required for the sensor signal input step S1. A sensor input / output connection unit 110 that receives each fuel injection amount signal of T);
A main control device (120) connected to the sensor input / output connection unit (110) to perform an engine inspection analysis method through fuel injection amount analysis of the compression ignition engine vehicle according to any one of claims 2 to 4;
A display unit 130 connected to the main control unit 120 and visually displaying an engine combustion state inspection analysis result and a result thereof;
An operation input unit 140 connected to the main control unit 120 and receiving a user's operation input; Engine inspection analysis device (100) through the fuel injection amount analysis of the compression ignition engine vehicle, characterized in that comprising a.

The method according to claim 5,
The fuel injection quantity analysis of the compression ignition engine vehicle is connected to the main control device 120 by using any one or more of the wireless communication module 150 or the internet network 160 connected to the main control device 120. External terminal device 170 that can query the performance results of the engine inspection analysis method through; Engine inspection analysis device (100) through the fuel injection amount analysis of the compression ignition engine vehicle, characterized in that further comprises a.

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