KR100301400B1 - Knocking control method and knocking control system - Google Patents

Abstract

PURPOSE: In an electronic control of an engine of an automobile, a knocking sensor is installed. A detected value of the knocking sensor is used for detecting engine knocking of a constant speed driving and an acceleration driving, and for learning-control. CONSTITUTION: A knocking sensor is mounted to a cylinder block of an engine to detect engine knocking. A knocking is decided by the signal of the knocking sensor. If it is decided as a knocking, an engine ignition time is decided by an information about ignition time stored in a memory in a map type. The map is divided into a normal state map and an excessive state map by the sensed value. A knocking control is carried out by the information whether it is a normal state or an excessive state. The map information is updated by the controlled result.

Description

Knocking control method and knocking control system for automobiles {KNOCKING CONTROL METHOD AND KNOCKING CONTROL SYSTEM}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electronic control of an automobile engine, and more particularly to a method for controlling knocking of an engine.

The present invention provides a knocking control method of a vehicle in which a knock detection sensor is installed in an electronic control of a vehicle engine, and the knock value of the engine can be detected and learning control can be performed at the same time in the constant speed and acceleration state of the engine using the detected value therefrom. An object is to provide a knocking control system.

In a vehicle, there is a knocking phenomenon in which a flame wave in a combustion chamber strikes an engine wall while the vehicle is driving.

In general, when combustion starts in the combustion chamber of the engine, the combustion wave generated around the ignition point is gradually transferred to the non-combustion gas around the lapse of time.

On the other hand, unburned gas at the periphery is compressed in accordance with the temperature of the heated combustion chamber wall or the like before the normal combustion wave arrives, and the temperature is raised to reach the self-ignition temperature. Then, the entire unburned gas around the combustion chamber wall causes spontaneous ignition and at the same time violent combustion, and the pressure increase generated at this time generates noise like tapping the combustion chamber wall with a small hammer.

Knocking in the engine is not just a noise problem, but heat transfer is improved by the vibration of the combustion gas.If this condition persists, the valve, spark plug electrode, or piston may overheat, causing damage to the engine. It is often the cause of damage.

The above-mentioned knocking phenomenon of the engine is related to the boost pressure, intake temperature, etc., but it is closely related to the ignition timing of the engine.If the ignition timing of the engine is accelerated (advance correction), the knocking phenomenon becomes severe and the ignition timing of the engine is slowed down. The knocking phenomenon disappears when the lower surface is corrected.

In addition, the above-described knocking phenomenon may be used as a means for confirming combustion efficiency of the engine.

That is, knocking generally has a negative effect on the engine, but when the combustion efficiency of the engine is the highest, a low profile that can draw the maximum torque from the engine is before and after the ignition period that starts knocking. Therefore, when the engine is operated at the boundary between the light knocking state and the non-knocking state, it is most advantageous in terms of output and fuel efficiency of the engine.

For the above reasons, a method of installing a knocking sensor using a piezoelectric piezoelectric effect on the cylinder block of the engine to detect the knocking state of the engine, delaying the ignition timing of the engine when the knocking occurs, and pulling the ignition timing otherwise. This ensures optimal control of the engine's ignition timing.

For the above reasons, a method of installing a knocking sensor using a piezoelectric piezoelectric effect on the cylinder block of the engine to detect the knocking state of the engine, delaying the ignition timing of the engine when the knocking occurs, and pulling the ignition timing otherwise. This ensures optimal control of the engine's ignition timing.

1A and 1B illustrate a process of controlling such a conventional knocking phenomenon. When there is a knocking phenomenon, the output of the knocking sensor has a peak at a time point of 6 to 8 dB, and thus filtering to detect such a phenomenon. The number of times the signal has exceeded a predetermined range (knock determination criteria) is counted to determine the strength of knocking, and the ignition timing is perceived or advanced as shown in FIG. 1B so that the ignition timing is controlled at the knocking limit.

The present invention is to control the knocking phenomenon of the engine described above, by using the detection value of the knocking sensor installed in the cylinder block of the engine, the engine RPM, the engine water temperature, the opening degree of the throttle valve, etc. to determine the current state of the engine, It is a technical task to provide a knocking control method and a control system for learning and controlling the knocking of the vehicle into a steady state and a transient state.

A detecting step of detecting knocking of the engine using a knocking sensor installed in the cylinder block of the engine; A determination step of determining whether to knock based on a signal of the sensor detected in the step; In the knocking control method, when the engine knocking is determined in the above step, the engine ignition timing is determined by determining the engine ignition timing according to the information on the ignition timing set and stored in the form of a map in a storage place.

In the method of perceptual control of the engine ignition timing, the map is divided into a steady state map and a transient state map according to the detected sensor value, and is set or updated. A knocking control method for a vehicle, characterized in that the knocking control is performed by classifying a transient state and the map information is updated according to the control result.

Knocking sensor, crank angle sensor, water temperature sensor, engine RPM sensor, ignition coil, throttle position detection sensor, a memory for storing a map which is information on the timing of ignition, A knocking control system for a vehicle comprising an igniter for determining an engine ignition timing and updating a set value according to information set in a map based on information from a sensor;

The memory is divided into a steady state map and a transient state map, and is set or updated. The controller classifies the steady state and the transient state based on the data from the sensor and refers to the above map. It provides a knocking control system for a vehicle, characterized in that it is a controller which executes the control for row knocking and updates the map according to the control result.

Particularly preferably, in the knocking control system, the knocking sensor is a single knocking sensor installed at the most suitable position of the cylinder of the engine; The storage location is a storage location for setting a map of the ignition timing of the steady state and the transient state of the engine; The controller is a controller for independently analyzing and processing information from the knock sensor, controlling knocking using the result and the map stored in the storage location, and updating the map using the control result. Provide a control system

1A is a diagram showing a detection waveform of a detection sensor when knocking of an engine occurs;

1B is a view for explaining knocking detection and control of a conventional knocking control system;

2 is a view schematically showing an execution procedure of a knocking control method of a vehicle according to the present invention;

3 is a configuration diagram of a knocking control system for a vehicle according to the present invention;

4 is a timing diagram showing a state in which an integrator accumulates a knocking signal in a knocking control of a vehicle according to the present invention;

5 is a view for explaining a knocking control method of a vehicle according to the present invention.

<Description of Symbols for Main Parts of Drawings>

1: knocking sensor 14: memory 15 electronic controller

Hereinafter, the configuration and operation of an engine knocking control method and a control system for a vehicle according to the present invention will be described with reference to the accompanying drawings.

2 is a diagram illustrating a configuration of a knock control method for a vehicle according to the present invention, in which signal processing is performed to receive a knocking signal from a sensor and determine knocking from a detection step to an integration step, and the processing step is knocking. In this case, the control process in the electronic control apparatus is executed.

3 is a view showing a schematic configuration of a knocking control system of a vehicle according to the present invention.

In the detecting step of FIG. 2, knocking of the engine is detected using a knocking sensor installed in the cylinder block of the engine.

The knocking sensor uses a conventional method, and mainly a detection method using a piezoelectric element is preferable, and the installation position is preferably installed at a place where all knocking signals generated in each cylinder are well captured.

The output of the knocking sensor can be cut off by the controller as a means for measuring and eliminating the noise of the circuit itself (Zero Test).

The output from the knocking sensor is gain-controlled, filtered, and rectified in the rectifier by a full range within the amplifier.

)을 연산하게 된다(도4).Based on the integrated result, the controller determines whether or not knocking. When the controller signal is turned on, the integrator determines the current knock detection value as follows.

) Is calculated (FIG. 4).

At this time, the base noise value K_b in Equation 1 is obtained as shown below using the integrated (Zero Test) value obtained while the output of the knocking sensor is cut off.

K_b = (S _int × W _k ) / 100'H + K ₀

At this time, in Equation 2, S _int : integrator tear, W _k : knock signal accumulation (integration) period, and K ₀ : integration initial value of zero test.

The integrator slope (S _int ) is also obtained through the zero test in the following way.

S _int = 100'H × (K ₁ -K ₀ ) / W ₀

At this time, K ₁ : Integral final value of zero test, W ₀ : Duration of zero test

The knock detection value K _int obtained as a result of the foregoing is compared with the comparison reference value K _ref , wherein the comparison criterion is obtained by first filtering the knock detection value.

In other words,

K _ref (i) = (1-α) × K _ref (i-1) + α × K _int (i)

In this case, α is a filtering gain to distinguish the values in the steady state from the acceleration (transient) state.

As a result of maturity, the reference value is obtained by filtering the knock detection shade, so that even if the knock detection value (K _int ) changes significantly, the comparison reference value (K _ref ), which is the result, shows a slow operation. On the other hand, the value suddenly changes significantly, while the comparison value of the first filtering of the knock detection value changes slowly, so when the difference between these two values increases, the occurrence of knocking can be confirmed.

On the other hand, after the determination of knocking, the comparative reference value Kref is recalculated in order to make up for the sensitivity of the determination.

The gain adjusting step of FIG. 2 is a means for limiting the knocking signal detected and transmitted from the sensor to a certain range, and the amplification gain is changed by the control of the controller.

Since the voltage range recognized by the controller, which is a digital signal processor, is limited (0V to 5V), it is not possible to distinguish between weak and weak when the signal transmitted to the controller is close to 5V. The size difference is meaningless.

Therefore, the controller can change the gain and the reference value of the amplifier so as to distinguish the difference between the aforementioned signals.

The signal for judging whether the controller reduces or increases the magnitude of the above-described gain is a variable comparison reference value K which is a primary filtering value of the current knock detection value K _int obtained by integration in the integration step of FIG. 2. _ref ).

In other words, if the integral value is too large, the comparison reference value is also increased, and if the value exceeds the reference maximum value (K _max ref) (K _ref > K _{max ref} ), the gain is reduced by the following method.

Cut the reference value in half (K _ref = K _ref / 2), and also set the initial value of the program's operation to K _amp = K _amp -1 (in this case, the actual gain is halved).

On the other hand, if the integral value becomes too small, the comparison reference value becomes smaller, so when the value falls short of the reference minimum value (K _{min ref} ) (K _ref <K _{min ref} ), the reference value is doubled (K _ref = K _ref × 2). Also, the initial value of the program operation is set to K _amp = K _amp + 1 (in this case, the actual gain is doubled).

In the above-described method, a comparison reference value for knocking and a current knocking detection value are obtained based on the detection value of the sensor, and then the comparison is made to determine whether knocking is performed.

On the other hand, during knocking detection, the signal from the knocking detection sensor installed in the cylinder of the engine block is processed to determine the dew which is knocked in the combustion chamber of the cylinder, and also the acceleration state (transient state) as well as the constant speed state (steady state). The above detection is also made.

Next, after the knocking of the engine is detected by the above-described method, the process of learning this in the steady state or the transient state of the engine and applying the learning result will be described.

This process is performed by dividing the normal state and the transient state by the controller of FIG. 3, various sensors, and a storage device.

5 is a control flow diagram schematically illustrating this process, and when knocking is detected, learning and control are performed by classifying the transient state and the steady state from the results of various sensors.

In the first path for processing in the case where knocking is detected in Fig. 5, the end of the process is performed by performing knock control in a steady state based on a map input to the storage device through learning about the cylinder of the engine in advance (instantaneous correction). The second path is terminated by performing the knocking control in the normal state based on the map input to the storage device through the learning of the engine in advance (instantaneous correction), and updating the map with the instantaneous correction value. Ending by performing knocking control in the transient state (acceleration state) based on the map stored in advance in the engine and stored in the engine, and the fourth path is learned in advance for the cylinder of the engine. The knock control in the transient state is performed on the basis of the map stored in the table, and the process is finished by updating the map according to the result.

That is, in the above-described process, the first path and the second path mean a processing process in a steady state in which the fuel injection state of the gin is in a stable state. When the learning condition is off and on, respectively, The third path and the fourth path are the processing paths when the learning condition is off and on, respectively, as the processing conditions in the acceleration state while the throttle valve of the engine is opened.

Both the first path and the second path are in a normal state and are distinguished according to the current water temperature state of the engine, and the ignition timing perception control is performed according to the stored map in advance with the first path in the state above the first reference water temperature T _ref1 . The perceptual correction amount is determined because the state is more unstable than when the second reference water temperature (T _ref2 > T _ref1 ) is exceeded, and the learning value (map) is updated using the result.

At this time, the first quasi-water temperature is suitable to about 40 degrees Celsius, and the second reference temperature is suitable to about 70 degrees.

In order to find the correction amount on the map as a condition for progressing to the first path and the second path, the current load state and the current engine RPM data are used.

This is because the creation of the map is made on the basis of the engine speed and the current load of the engine as shown in the storage device of FIG.

In particular, the updating of the learning value in the second path consists of updating the instantaneous correction value, and the learning value is applied only to the initial value of the instantaneous correction at the time of entering the second path or the state transition from the first path to the second path. The instantaneous correction is made from the initial value.

On the other hand, both the third path and the fourth path are cases in which the vehicle is in an acceleration state, and are distinguished from the first and second paths by using the angular velocity at which the engine's throttle valve is opened. As a result, it is relatively stable, and if the third step of performing perceptual control on the basis of the learned map is relatively unstable and knocking occurs again during the control of the ignition timing, it is necessary to perform the perceptual control and update the learned map. It is decided as the fourth route.

As a result, the transition condition to the third path is a case where the water temperature exceeds a certain value, the opening degree of the throttle valve exceeds a certain degree, and the vehicle speed exceeds the sum of the reference vehicle speed and the predetermined correction value for the acceleration judgment.

Further, the transition condition to the fourth path is when the water temperature is about a certain degree (about 40 degrees Celsius or more, and the amount of change per hour (based on 10 msec) of the opening degree of the throttle valve exceeds a certain degree.

In addition, the application of the learning value to the knocking during acceleration is for the initial perception amount, and after the initial step, the forward control is performed and the learning value is updated when the knocking during the speed perception correction occurs.

With the above-described path, the electronic control device monitors the knocking state of the engine during acceleration as well as during normal driving, and when knocking occurs, it is learned in the normal state and the transient state and determines the perceptual correction amount according to the stored map to ignite the ignition coil. Sending a signal controls knocking.

If the result of perceptual correction is to replace the conventional map, the map is updated according to the learning theory.

By providing a vehicle knocking control method and a knocking control system having the above-described configuration, unlike the related art, it is possible to control not only the normal state of the vehicle but also the transient state in the acceleration state, thereby enabling accurate knocking control. .

Claims (12)

(delete) (delete) (delete) (Correcting) a detecting step of detecting knocking of the engine using a knocking sensor installed in the cylinder block of the engine; A determination step of determining whether to knock based on a signal of the sensor detected in the step; In the knocking control method, when the engine knocking is determined in the above step, the engine ignition timing is determined by determining the engine ignition timing according to the information on the ignition timing set and stored in the form of a map in a storage place. In the method of intelligently controlling the engine ignition timing, the map is divided into a steady state map and a transient state map by the value of the detected sensor, and the map is set or updated. A knocking control method for a vehicle, characterized in that when the transient state is classified, knocking control is executed, and the map information is updated according to the control result. (Correction) The method according to claim 4, wherein the method for controlling perception of the engine ignition timing comprises: detecting a water temperature of the engine; The engine is classified into a steady state and a transient state based on the water temperature detection result of the engine, and when the detected water temperature value exceeds the first reference water temperature T _ref1 , the ignition timing is pre-learned in the first path. And performing the perceptual control, and if the second reference water temperature (T _ref2 > T _ref1 ) is exceeded, determining the perceptual correction amount and updating the result according to the result of the knocking control. (Correct) The method according to claim 4 or 5, wherein the method for retarding the engine ignition timing comprises: detecting a vehicle speed; If the detected vehicle speed exceeds a reference vehicle speed for acceleration determination, determining that the engine is in a transient state (acceleration state) based on a map stored in advance in the storage device and executing knocking control. The knocking control method of a vehicle characterized by the above. (delete) (delete) (delete) Knocking sensor, crank angle sensor, water temperature sensor, engine RPM sensor, ignition coil, throttle position detection sensor, a memory for storing a map which is information on the timing of ignition, A knocking control system for a vehicle comprising an igniter for determining an engine ignition timing and updating a set value according to information set in a map based on information from a sensor; The memory is divided into a steady state map and a transient state map, and is set or updated. The controller classifies the steady state and the transient state based on the data from the sensor and refers to the above map. A knocking control system for a vehicle, characterized in that for performing a knocking control and updating the map according to a control result. (Correction) The controller of claim 10, wherein the controller classifies the controller into a steady state and a transient state based on a value of the detected water temperature sensor, and wherein the detected water temperature sensor exceeds the first reference water temperature T _ref1 . The ignition timing perception control is performed according to the pre-learned and stored map in one path, and when the value of the detected water temperature sensor exceeds the second reference water temperature (T _ref2 > T _ref1 ), the perceptual correction amount is determined and the result And a knocking control system for updating the learning value (map) accordingly. (Correction) The transient state (acceleration state) according to claim 10 or 11, wherein the controller is based on a map stored in advance in the storage device, which is learned in advance about the engine when the detected vehicle speed exceeds a reference vehicle speed for acceleration determination. Knocking control system of the vehicle, characterized in that for executing the knocking control.

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