KR102452705B1 - Early learning method for cvvd position and cvvd system - Google Patents

Abstract

According to the present invention, if the Continuously Variable Valve Duration (CVVD) ON state according to the engine start is confirmed in the CVVD ECU (Electronic Control Unit), the short (SHORT) position verification for the control shaft position before the CVVD duration control operation is followed by the long (LONG) It relates to a CVVD position early learning method, characterized in that it includes a duration position learning control in which position verification is performed.
The present invention provides a long (LONG) position verification following the short position verification of the control shaft in the CVVD (Continuously Variable Valve Duration) ON state after starting the engine and starting the multi point injection (MPI) system. LONG) It relates to a CVVD system characterized in that it includes a CVVD ECU (Continuously Variable Valve Duration Electronic Control Unit) that performs early position learning before CVVD duration control operation.

Description

Continuously variable valve duration (CVVD) position early learning method and CVVD system

The present invention relates to continuously variable valve duration (CVVD) position control, and more particularly, to a CVVD system in which early CVVD position learning capable of enhancing fail safe performance for a CVVD long position is implemented. will be.

The CVVD (Continuously Variable Valve Duration) system applies an actuator (or motor) and valve lift to change the valve duration instead of simultaneously changing the valve opening/closing timing with a fixed valve duration like CVVT. It can be changed according to the operating state of

Therefore, the CVVD system controls the long-short duration as the wheel housing of the control shaft moves up and down through the rotation of the control shaft. It maintains the startability of the engine by securing the correct starting position.

For example, in the short position and the long position, 0° may be defined as a short position and 173° may be defined as a long position in a 360° rotation angle.

However, the CVVD system has a problem in that the engine may be turned off due to the long position remaining at the default due to a failure during long-short duration control and may fall into impossible restart in the future.

In order to solve the above problems, the fail safe performance for the long position is strengthened by learning the short and long positions for the control shaft position before CVVD control at the same time as the engine is started. In particular, the purpose of this is to provide a CVVD location early learning method and CVVD system that prevents the engine from falling out of the long position in the case of a default due to a failure and unable to restart in the future.

According to the present invention, if the Continuously Variable Valve Duration (CVVD) ON state according to the engine start is confirmed in the CVVD ECU (Electronic Control Unit), the short (SHORT) position verification for the control shaft position before the CVVD duration control operation is followed by the long (LONG) It is a CVVD position early learning method, characterized in that it includes a duration position learning control in which position verification is performed.

The present invention provides a long (LONG) position verification following the short position verification of the control shaft in the CVVD (Continuously Variable Valve Duration) ON state after starting the engine and starting the multi point injection (MPI) system. LONG) It is a CVVD system characterized in that it includes a CVVD ECU (Continuously Variable Valve Duration Electronic Control Unit) that performs position early learning before CVVD duration control operation.

The present invention can prevent the start-up delay off, etc. by early learning (using a voltage value) the valve position for determining the CVVD position.

In addition, it is possible to improve marketability and prevent quality problems by satisfying the OBD (On Board Diagnosis) regulations when responding to start delays and EM by responding to the recent tightening of fuel economy regulations (securing excellent fuel efficiency compared to gasoline).

1 is a flowchart of a CVVD location early learning method according to the present invention.
2 is a configuration example of a CVVD system according to the present invention.
3 is an embodiment of the operating state of the CVVD system according to the short/long position.
4 is an embodiment of shortening the long position variable learning time through the short/long position-time diagram.

In order to fully understand the present invention, preferred embodiments of the present invention will be described with reference to the accompanying drawings. Embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited to the embodiments described in detail below. This embodiment is provided to more completely explain the present invention to those of ordinary skill in the art. Accordingly, the shape of elements in the drawings may be exaggerated to emphasize a clearer description. It should be noted that the same configuration in each drawing is sometimes illustrated with the same reference numerals. Detailed descriptions of well-known functions and configurations determined to unnecessarily obscure the gist of the present invention will be omitted.

According to the present invention, when the Continuously Variable Valve Duration (CVVD) ON state according to the engine start is confirmed in the CVVD ECU (Electronic Control Unit), the short position of the control shaft 140 before the CVVD duration control operation is verified. It relates to a CVVD position early learning method, characterized in that it includes a duration position learning control in which the subsequent long position verification is performed.

Referring to FIG. 1, the CVVD position early learning method includes control before CVVD operation (S10, S20, S30, S40), CVVD SHORT DUTY control for short position verification (S50.S60, S60'), and long ) CVVD LONG DUTY control for position verification (S70.S80, S80') and early position learning completion control (S90, S90', S100) are implemented.

Referring to FIG. 2 , the CVVD system 100 is linked with a camshaft 170 having a cam 160 , and is controlled by a CVVD ECU 110 , the CVVD ECU 110 is coupled with an actuator 130 . A control shaft 140 equipped with a wheel 150 to perform SHORT/LONG duration control and a Hall sensor 120 for detecting the position of the SHORT/LONG are included.

In particular, the CVVD ECU 110 performs early learning for short/long by using the count signal of the hall sensor 120 as a threshold, and uses the early learning result to control the engine. output to the ECU 200 .

Therefore, the CVVD ECU 110 acts as a control subject for the CVVD position early learning method, and the actuator 130 serves as a control target for the CVVD position early learning method.

Hereinafter, the CVVD location early learning method of FIG. 1 will be described in detail with reference to FIGS. 2 to 4 .

In the control before the CVVD operation (S10, S20, S30, S40), after the engine is driven (S10) and the MPI system is driven (S20), when the CVVD is turned on (S30), determining the entry mode (S40) proceeds.

Referring to FIG. 3 , the control shaft 140 moves the wheel 150 up and down as it rotates, and the up and down movement of the wheel 150 is a short (SHORT) position and a long (LONG) position of the control shaft 140 . to form

Therefore, the CVVD ECU 110 controls the CVVD SHORT DUTY and the CVVD LONG DUTY of the actuator 130 to a short position and a long position, respectively.

In particular, the CVVD ECU 110 detects information of a multi point injection (MPI) system in connection with the ECU 200 and checks rpm (revolution per minute) and load of the CVVD system 100 in connection therewith. to change the CVVD LONG DUTY for long position verification.

For example, in the entry mode step (S40), the entry mode is divided into 1, 2, 3 entry mode, and the 1, 2, 3 entry mode is the number of rotations of the actuator 120 for the long (LONG) as shown in FIG. 4 . can be divided into 200, 400, and 500 rpm to match 60%, 45%, and 30% DUTY, respectively.

After that, in the CVVD SHORT DUTY control (S50, S60, S60'), the movement to the shot position is performed with a fixed duty (S50), and the shot position is determined with a threshold value (S60), and when the threshold value is satisfied The short position determination is continued until (S60')

For example, in the step of moving the shot position ( S50 ), the fixed duty may be matched to 30% DUTY by fixing the number of rotations of the actuator 120 for the shot to 200 rpm as shown in FIG. 4 .

For example, in the short position determination step S60 , the threshold value is a count signal for the signal of the hall sensor 130 , and the short position determination is applied as follows.

Short position judgment: Hall sensor count > A

Here, 35 ms may be set as a threshold value of A, but may vary depending on the operating conditions of the CVVD system 100 .

Then, in the CVVD long duty control (S70, S80, S80'), after the control shaft reaches the short position, the control shaft moves to the long position (S70), and is positioned at the threshold value in the same way as the short position is determined. The determination is performed (S80), and if this is not satisfied, the movement to the long position is continued (S80').

For example, in the long position moving step (S70), the variable duty is a first entry mode in which 200 rpm of the actuator 120 for LONG is matched with 60% DUTY, 400 rpm is matched with 45% DUTY, as shown in FIG. The second entry mode may be divided into a third entry mode in which 500 rpm is matched with 30% DUTY.

Therefore, the long position movement may be moved by selectively applying the first, second, and third entry modes or by sequentially applying the first, second, and third entry modes.

For example, in the long position determination step S80 , the threshold value is a count signal for the signal of the hall sensor 130 , and the long position determination is applied as follows.

Long position judgment: Hall sensor count > A

Here, 35 ms may be set as a threshold value of A, but may vary depending on the operating conditions of the CVVD system 100 . Therefore, the same threshold value is applied to short position judgment and long position judgment.

For example, in the long position determination step S80 , the long position determination may be learned by selective control of the first, second, and third entry modes or by sequential control of the first, second, and third entry modes.

After that, in the early position learning completion control (S90, S90', S100), when the control shaft reaches the long position, learning is completed (S90), and at this time, the long position learning value is also updated at the same time (S90) '), the CVVD ECU outputs a CAN message to the upper ECU, and the position learning is completed (S100).

For example, in the step of updating the long position learning value (S90'), the result of the long position early learning is stored and updated using the memory of the CVVD ECU.

4, the CVVD position learning method according to the present invention increases the efficiency by shortening the learning time from the short position (0%) to the long position (100%). When the entry mode is LONG 200rpm/60% DUTY (dashed line), it takes a time of T2 until learning is completed, whereas when the entry mode is LONG 500rpm/30% DUTY, it can be confirmed that it takes time of T1 . In this way, it is possible to confirm the effect of shortening the learning time by determining the entry mode in advance according to the long position and proceeding with the learning.

In FIG. 4 , a total of three modes are applied as the entry mode of the CVVD position early learning method, but this is only an exemplary embodiment and may be variously changed and applied according to the operating conditions of the engine.

The embodiments of the present invention described above are merely exemplary, and those of ordinary skill in the art to which the present invention pertains will appreciate that various modifications and equivalent other embodiments are possible therefrom. Therefore, it will be well understood that the present invention is not limited to the forms recited in the above detailed description. Therefore, the true technical protection scope of the present invention should be determined by the technical spirit of the appended claims. It is also to be understood that the present invention includes all modifications, equivalents and substitutions falling within the spirit and scope of the invention as defined by the appended claims.

1: engine
100: CVVD system
200 : upper ECU
110: CVVD ECU
120: hall sensor
130: actuator
140: control shaft
150: wheel
160 : cam
170: camshaft
T1: 1st long position variable learning time (LONG 500rpm/30% DUTY)
T2: 2nd long position variable learning time (LONG 200rpm/60% DUTY)

Claims (18)

When the CVVD (Continuously Variable Valve Duration) ON status according to engine start is confirmed in the CVVD ECU (Electronic Control Unit), a short for the control shaft position before CVVD duration control operation (SHORT) followed by a long position verification a duration position learning control in which position verification is performed is included;
The duration position learning control may include: determining an entry mode of the position of the control shaft;
After moving the control shaft position to the short position with CVVD SHORT duty, verifying the short position with the voltage value detected by the count signal of the hall sensor at the short position;
After moving the control shaft position to the long position with CVVD long duty, verifying the long position with the voltage value detected at the long position; CVVD location early learning method, characterized in that performed as. delete According to claim 1,
The determination of the entry mode is
CVVD location early learning method, characterized in that it is made in the starting state of the MPI (Multi Point Injection) system and the CVVD LONG DUTY is changed. 4. The method of claim 3,
The CVVD position early learning method, characterized in that the change of the CVVD long duty is rpm (revolution per minute) and load (load) for the operation of the CVVD is considered. 5. The method of claim 4,
The rpm is
The CVVD position early learning method, characterized in that the rpm classification is made so that the CVVD long duty is changed, while a fixed value is applied to the CVVD short duty. delete According to claim 1,
The count signal is set to a threshold, and each of the short position verification and the long position verification consists of satisfying a condition for the threshold value. learning method. 8. The method of claim 7,
The threshold is
CVVD location early learning method, characterized in that the same condition is applied to the short (SHORT) location verification and the long (LONG) location verification. 9. The method of claim 8,
The CVVD location early learning method, characterized in that the threshold (threshold) is 35ms. According to claim 1,
The duration position learning control is,
updating the long position verification to a long position learning value and outputting a duration position learning end signal; CVVD location early learning method, characterized in that it further comprises. 11. The method of claim 10,
The update of the long (LONG) location learning value is
CVVD location early learning method, characterized in that it varies according to the entry mode. After starting the engine and starting the MPI (multi point injection) system, in the CVVD (Continuously Variable Valve Duration) ON state, the long position through the long position verification followed by the short position verification of the control shaft CVVD ECU (Continuously Variable Valve Duration Electronic Control Unit) that performs early learning before CVVD duration control operation; includes;
The CVVD ECU, wherein the CVVD ECU outputs the SHORT DUTY of the short position verification as a fixed value while outputting the LONG DUTY of the long position verification as a variable value. 13. The method of claim 12,
The CVVD ECU is linked to a Hall sensor, and the Hall sensor transmits signals of the short position verification and the long position verification to the CVVD ECU. 14. The method of claim 13,
The Hall sensor generates the signal as a count signal, and the CVVD ECU determines the short position verification and the long position verification using the count signal, respectively. 15. The method of claim 14,
CVVD system, characterized in that the count signal is 35ms. delete 13. The method of claim 12,
The variable value is
A CVVD system, characterized in that the entry mode is divided into an entry mode in consideration of rpm (revolution per minute) and load of the CVVD, wherein long duty matching is performed for each rpm. 13. The method of claim 12,
The CVVD ECU is
CVVD system, characterized in that the result of the long (LONG) location early learning is updated in memory.

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