JP4874920B2 - Control device for variable valve mechanism - Google Patents

Description

  The present invention relates to a control device for a variable valve mechanism that varies the operating characteristics of intake / exhaust valves (engine valves) in an internal combustion engine, such as lift amount (or / and operating angle) and valve timing.

Patent Document 1 discloses that control using a reference model of response characteristics is performed in a variable valve mechanism (variable valve timing mechanism) that changes valve timing.
This sets a reference model that responds with desired characteristics to the target value of the variable valve mechanism, and sets the feedforward operation amount so that the response of the variable valve mechanism follows the reference model response, The output of the reference model and the actual output of the variable valve mechanism will be different due to the variation of the variable valve mechanism over time and variations due to operating conditions, so the output of the reference model and the variable valve mechanism will be absorbed to absorb this deviation. Based on the deviation from the actual output, a feedback operation amount by PID or the like is set, and control is performed based on the feedforward operation amount and the feedback operation amount.
JP 2003-336528 A

  By the way, in a control device for a variable valve mechanism such as that disclosed in Patent Document 1, a drive reaction force from a drive cam is periodically applied to the variable valve mechanism as the engine valve is opened and closed, and an output section of the variable valve mechanism Cause vibration. In response to feedback control that suppresses the vibration, an excessive amount of operation is output, resulting in deterioration of fuel consumption due to an increase in power consumption, heat generation of the drive circuit and motor, and a decrease in durability.

Therefore, it is conceivable to prevent the operation amount from becoming excessive by smoothing the actual response value compared with the reference response value in the feedback control by the filter processing.
However, since the filtered value used for feedback control has a large phase difference with respect to the actual response value of the variable valve mechanism, there arises a problem that control performance such as responsiveness and convergence is impaired.

  The present invention has been made paying attention to such a conventional problem, and in the norm response control of the variable valve mechanism, the response and convergence are satisfied while suppressing an excessive operation amount. The purpose is to do.

For this reason, the invention according to claim 1
Equipped with a variable valve mechanism that changes the valve opening characteristics of the engine valve,
Target value calculating means for calculating a target value of the variable valve mechanism corresponding to a target value of the valve opening characteristic of the engine valve;
Normative response value calculating means for calculating a normative response value when the variable valve mechanism is caused to respond with a response characteristic defined with respect to the target value;
A feedforward manipulated variable calculating means for calculating a feedforward manipulated variable for causing the variable valve mechanism to respond with a response characteristic defined with respect to the target value;
Feedback manipulated variable calculating means for calculating a feedback manipulated variable for eliminating a deviation between the reference response value and the actual response value of the variable valve mechanism;
Based on the feedforward operation amount and the feedback operation amount, an operation amount calculation unit that calculates an operation amount output to the drive unit of the variable valve mechanism,
In a control device for a variable valve mechanism configured to include:
In order to remove the influence of the reaction force torque from the engine side, a filter means for smoothing the feedforward manipulated variable and the feedback manipulated variable using the same smoothing characteristic is provided.
The operation amount smoothed by the filter means is output to the drive means of the variable valve mechanism.

  According to such a configuration, an increase in the amplitude of the feedback operation amount is smoothed by the filter unit and output to the drive unit with respect to the drive reaction force applied periodically, and thus the drive force is prevented from becoming excessive. In addition to suppressing heat generation and fuel consumption deterioration, by providing the filter means immediately before the drive means, calculating the feedback manipulated variable using the actual response value as it is, the actual response value due to phase delay due to smoothing And the reference response value are eliminated, and control can be performed so that the reference response value can be accurately followed.

The invention according to claim 2
In addition to the configuration of claim 1,
The normative response value calculating means is configured to calculate the normative response value based on the prescribed response characteristic and the smoothing characteristic of the filter means.
According to such a configuration, by giving the response delay of the variable valve mechanism due to smoothing to the reference response value as well, the phase difference between the reference response value used in the feedback control and the actual response value is eliminated, and undulation and fluctuation occur. Can be suppressed.

The invention according to claim 3
In the control device for the variable valve mechanism having the same basic configuration as in claims 1 and 2,
First filter means for smoothing the feedforward manipulated variable;
Second filter means for smoothing the feedback manipulated variable;
An operation amount output means for outputting an operation amount obtained by adding the feedforward operation amount via the first filter means and the feedback operation amount via the second filter means to the drive means of the variable valve mechanism;
Determining means for determining whether or not the calculated value of the operation amount is equal to or greater than a maximum driving force of the driving means;
Normal smoothing by the second filter means at other normal times is stopped from when it is determined that the manipulated variable is greater than or equal to the maximum drive amount until less than the maximum drive force and a predetermined time elapses. Or smoothing switching means for switching so as to weaken,
Is provided.

With this configuration, when the target value changes with a ramp response or a step response with a small change amount, as in claim 2, it is possible to prevent excessive driving force and suppress heat generation and fuel consumption deterioration. Thus, the swell and fluctuation of the actual response value due to the phase delay accompanying the smoothing by the filter means can be suppressed.
In addition, when the amount of change in the target value is large and the calculated value of the manipulated variable is equal to or greater than the maximum driving force of the driving mechanism of the variable valve mechanism, the maximum driving force is saturated, the feedback control function does not work, and the norm response value Since the deviation between the actual response value and the actual response value increases, using a feedback manipulated variable smoothed by a filter degrades the convergence, but for a predetermined time after the saturated state is eliminated from the saturated state. When the deviation is to be absorbed by feedback control, smoothing by the second filter is stopped or weakened, and the use of a feedback operation amount that matches the actual deviation can prevent deterioration of convergence.

Embodiments of the present invention will be described below.
FIG. 1 is a system diagram of an internal combustion engine for a vehicle according to an embodiment.
In FIG. 1, an internal combustion engine 101 is a V-type engine composed of two banks on the left and right.
An electronic control throttle 104 is interposed in the intake pipe 102 of the engine 101, and the air that has passed through the electronic control throttle 104 is distributed to each bank and then to each cylinder.

In each cylinder, air is sucked into the combustion chamber 106 via the intake valve 105.
The combustion exhaust gas is discharged from the combustion chamber 106 via the exhaust valve 107, and then exhaust gas is collected for each bank and purified by the front catalyst 108a, 108b and the rear catalyst 109a, 109b provided for each bank.
The exhausts of the banks after being purified by the rear catalysts 109a and 109b merge and flow into the muffler 103, and are then released into the atmosphere.

The exhaust valve 107 is opened and closed by a cam pivotally supported by the exhaust side camshaft 110 while maintaining a certain lift, operating angle, and valve timing (center phase of the operating angle).
On the other hand, on the intake valve 105 side, operating angle / lift variable mechanisms 112a and 112b, which are first variable valve operating mechanisms for continuously changing the lift of the intake valve 105 together with the operating angle, are provided for each bank. It is also possible to apply a variable valve mechanism that makes only one of the lift and the operating angle variable.

Further, on the intake valve 105 side, there is a second variable valve mechanism that continuously and variably controls the center phase of the operating angle of the intake valve 105 by changing the rotational phase of the intake valve drive shaft relative to the crankshaft. Center phase variable mechanisms 113a and 113b are provided for each bank.
An electronic control unit (ECU) 114 with a built-in microcomputer has the electronic control throttle 104, the operating angle / lift variable mechanisms 112a and 112b, and the center phase variable so that a target intake air amount corresponding to the accelerator opening is obtained. The mechanisms 113a and 113b are controlled.

  The electronic control unit 114 includes an air flow meter 115 (flow meter) that detects the intake air flow rate of the engine 101, an accelerator sensor 116 that detects the amount of depression of the accelerator pedal, a crank angle sensor 117 that detects the rotation angle of the crankshaft, Detection signals from a throttle sensor 118 that detects the opening TVO of the electronically controlled throttle 104, a water temperature sensor 119 that detects the coolant temperature of the engine 101, and air-fuel ratio sensors 111a and 111b that detect the exhaust air-fuel ratio of each bank are input. Is done.

A fuel injection valve 131 is provided at the intake port portion upstream of the intake valve 105 of each cylinder.
The fuel in the fuel tank 132 is pumped to the fuel injection valve 131 by a fuel pump 133, and the fuel injection valve 131 is driven to open by an injection pulse signal (air-fuel ratio control signal) from the electronic control unit 114. Then, an amount of fuel proportional to the injection pulse width (valve opening time) is injected into the engine 101.

Next, the structure of the operating angle / lift variable mechanisms 112a and 112b and the center phase variable mechanisms 113a and 113b will be described with reference to FIGS.
In the engine 101 of this embodiment, a pair of intake valves 105, 105 are provided for each cylinder, and an intake valve drive shaft 3 that is rotationally driven by a crankshaft is above the intake valves 105, 105 in the cylinder row direction. Is supported rotatably.

A swing cam 4 that contacts the valve lifter 2a of the intake valve 105 and opens and closes the intake valve 105 is fitted on the intake valve drive shaft 3 so as to be relatively rotatable.
Between the intake valve drive shaft 3 and the swing cam 4, operating angle / lift variable mechanisms 112a and 112b for continuously changing the operating angle and valve lift amount of the intake valve 105 are provided.

Further, at one end of the intake valve drive shaft 3, a center phase variable for continuously changing the center phase of the operation angle of the intake valve 105 by changing the rotational phase of the intake valve drive shaft 3 with respect to the crankshaft. Mechanisms 113a and 113b are provided.
As shown in FIGS. 2 and 3, the operating angle / lift variable mechanisms 112 a and 112 b are rotatable relative to the circular drive cam 11 that is fixedly provided eccentrically to the intake valve drive shaft 3. A ring-shaped link 12 that fits externally, a control shaft 13 that extends substantially parallel to the intake valve drive shaft 3 in the direction of the cylinder row, a circular control cam 14 that is fixed to the control shaft 13 in an eccentric manner, A rocker arm 15 that is externally fitted to the control cam 14 so as to be relatively rotatable, and has one end connected to the tip of the ring-shaped link 12, and a rod-shaped link 16 connected to the other end of the rocker arm 15 and the swing cam 4 ,have.

The control shaft 13 is rotationally driven within a predetermined control angle range via a gear train 18 by an electric actuator 17 (motor).
With the above configuration, when the intake valve drive shaft 3 rotates in conjunction with the crankshaft, the ring-shaped link 12 moves substantially in translation through the drive cam 11 and the rocker arm 15 swings around the axis of the control cam 14. Then, the swing cam 4 swings through the rod-shaped link 16 and the intake valve 105 is driven to open and close.

Further, by changing the rotation angle of the control shaft 13, the axial center position of the control cam 14 serving as the rocking center of the rocker arm 15 is changed, and the posture of the rocking cam 4 is changed.
As a result, the operating angle and lift of the intake valve 105 continuously increase or decrease while the center phase of the operating angle of the intake valve 105 is kept substantially constant.
FIG. 4 shows the center phase variable mechanisms 113a and 113b.

  The center phase variable mechanisms 113a and 113b are fixed to a sprocket 25 that rotates in synchronization with a crankshaft, and a first rotating body 21 that rotates integrally with the sprocket 25 and a bolt 22a of the intake valve drive shaft 3 are fixed. A second rotating body 22 fixed to one end and rotating integrally with the intake valve drive shaft 3, and a cylinder meshed with the inner peripheral surface of the first rotating body 21 and the outer peripheral surface of the second rotating body 22 by a helical spline 26. Intermediate gear 23.

The intermediate gear 23 is connected to a drum 27 via a screw 28, and a torsion spring 29 is interposed between the drum 27 and the intermediate gear 23.
The intermediate gear 23 is biased in the retarding direction (left direction in FIG. 4) by a torsion spring 29. When a voltage is applied to the electromagnetic retarder 24 to generate a magnetic force, the intermediate gear 23 advances through the drum 27 and the screw 28. It is moved in the angular direction (right direction in FIG. 4).

In accordance with the axial position of the intermediate gear 23, the relative phase of the rotating bodies 21 and 22 changes, the phase of the intake valve drive shaft 3 with respect to the crankshaft changes, and the central phase of the operating angle of the intake valve 105 continues. Changes.
The electric actuator 17 and the electromagnetic retarder 24 are driven and controlled by a control signal from the electronic control unit 114.

The structure of the center phase variable mechanisms 113a and 113b is not limited to the above-described structure, and a known mechanism that makes the rotational phase of the intake valve drive shaft 3 (intake side camshaft) variable with respect to the crankshaft is applied. it can.
The electronic control unit 114 sets a target angle (target lift) of the control shaft 13 and feeds back an operation amount of the electric actuator 17 so that an actual angle detected by the angle sensor 32 approaches the target angle. Control.

  Further, the electronic control unit 114 performs intake air to the crankshaft from a signal from the drive shaft sensor 31 that outputs a detection signal at a predetermined angular position of the intake valve drive shaft 3 and a detection signal from the crank angle sensor 117. The rotational phase of the valve drive shaft 3 is detected, and the operation amount of the electromagnetic retarder 24 is feedback-controlled so that the detection result approaches the target rotational phase.

Next, details of control of the variable operating valve / operating angle / lift variable mechanisms 112a and 112b and the center phase variable mechanisms 113a and 113b will be described.
FIG. 5 is a control block diagram of the first embodiment of the variable operating angle / lift mechanism 112 (112a, 112b).
The target value calculation unit A is based on the engine operating state and the target value of the variable operating angle / lift mechanism 112 (target of the control shaft 13) corresponding to the target value (target operating angle) of the operating angle / lift characteristic of the intake valve 105. It calculates a rotation angle) theta _T.

Nominal response value calculation unit B receives the target value theta _T operating angle lift variable mechanism 112, nominal response value when the response according to the response characteristic of the provisions designer desires (nominal response characteristic) theta _M Is calculated. That is, the reference value θ _M is set as a transient target value that converges to the final target value θ _T with a desired response characteristic.
Specifically, the norm response characteristic R (s) for obtaining a stable response to the following dynamic characteristic (motion equation) of the variable operating angle / lift mechanism 112 shown in the following expression (1) is expressed by the expression (2) Then, the normative response value θ _M is calculated by the equation (3).

T = J (d ² θ / dt ² ) + μ (dθ / dt) + Kθ (1)
Where T: drive torque, θ: rotation angle of the control shaft 13 of the operating angle / lift variable mechanism 112, J: moment of inertia of the operating angle / lift variable mechanism 112, μ: friction coefficient of the operating angle / lift variable mechanism 112, K: Spring constant of operating angle / lift variable mechanism 112 R (s) = ω ² / (s ² + 2ζωs + ω ² ) (2)
S: Laplace operator, ω: frequency, ζ: damping coefficient θ _M = θ _T · R (s) (3)
The feedforward manipulated variable calculator C calculates and outputs a feedforward manipulated variable for causing the operating angle / lift variable mechanism 112 to respond according to the norm response characteristics.

Specifically, the feedforward transfer function F _FF (s) is a function obtained by inversely transforming the transfer function P (s) of the following dynamic characteristics of the operating angle / lift variable mechanism 112 as shown in the following equation (4). It is set as the product P ⁻¹ (s) · R (s) of P ⁻¹ (s) and the reference response characteristic R (s).
F _FF (s) = P ⁻¹ (s) · R (s) (4)
Then, the feedforward drive current i _FF is calculated by multiplying the input target value θ _T by the transfer function F _F (s) as in the following equation (5).

i _FF = F _FF (s) · θ _T (5)
When the drive current i of the electric actuator 17 is controlled by the drive voltage, it is converted into a feed-forward drive voltage V _FF to obtain the feed-forward drive current i _FF as a feed-forward operation amount and output.
Based on the deviation θ _ERR (= θ _M −θ _R ) between the reference response value θ _M and the actual response value (actual rotation angle) θ _R of the operating angle / lift variable mechanism 112, the feedback manipulated variable calculation unit D The feedback drive current i _FB is calculated by the following equation (6) using the proportional element P and the integral element I by the equation (5), converted into the feedback drive voltage V _FB as the feedback operation amount, and output.

i _FB = (P + I / s + Ds) · θ _ERR (6)
The filter processing unit E performs a smoothing process on the drive voltage obtained by adding the feedforward drive voltage _VFF and the feedback drive voltage _VFB, and uses the operating angle / lift variable mechanism 112 (electrically driven) as a final operation amount. Output to the actuator 17).
That is, while controlling the operating angle / lift variable mechanism 112 with the feedforward operation amount so as to respond according to the norm response characteristic, the deviation between the normative value and the actual value caused by the variation of the mechanism or the use condition is determined as the feedback operation amount. In the control to be absorbed by the motor, the calculated operation amount is filtered and output to the electric actuator 17.

  As a result, the actual response value of the electric actuator 17 driven by the manipulated variable after the filter processing is used as an actual response value that is fed back and compared with the reference response value. The vibration due to the reaction force is eliminated, and the feedback operation amount is prevented from becoming an excessive value so as to suppress the vibration, and the deterioration of the fuel consumption due to the increase in power consumption and the decrease in the durability due to the heat generation of the electric actuator 17 can be prevented.

Here, even when the actual response value is filtered to obtain the feedback value as in the conventional case, the above problem is solved, but the feedback value follows the reference response value, but the actual response value is advanced. Controlled to cause fluctuations.
On the other hand, by performing the filtering process on the operation amount as in the present embodiment, the actual response value and the feedback value become the same value, and the phase difference can be eliminated.

In the above embodiment, the phase difference between the actual response value and the feedback value is eliminated, but the response of the variable valve mechanism with respect to the manipulated variable remains in phase lag, resulting in swell and deterioration of convergence.
Therefore, in the second embodiment, the phase difference between the reference response value and the response of the variable valve mechanism is eliminated.

Therefore, the filter processing unit E and the variable operating angle / lift mechanism 112 are considered as one plant.
A control block diagram of the second embodiment is shown in FIG.
The reference response value calculation unit B calculates the reference response characteristic R (s) ′ for the plant in which the filter processing unit E and the variable operating angle / lift mechanism 112 are combined, as shown in the following equation (7). the nominal response characteristics of the variable mechanism 112 R (s), and sets the filter characteristic F (s) as synthesized calculated value, calculates the nominal response value theta _M by equation (8).

R (s) '= R (s) · F (s) (7)
θ _M = θ _T・ R (s) '= θ _T・ R (s) ・ F (s) (8)
The feedforward transfer function F _F (s) in the feedforward manipulated variable calculation unit C is set as follows.
A transfer function P (s) ′ of the plant in which the filter processing unit E and the operating angle / lift variable mechanism 112 are combined is expressed by the following equation (9).

P (s) '= F (s) · P (s) (9)
Therefore, the feedforward transfer function F _FF (s) is set as follows based on the transfer function P (s) ′ and the reference response characteristic R (s) ′ of these plants.
F _FF (s) = P ⁻¹ (s) ′ · R (s) ′
= F ^-1 (s), P ^-1 (s), R (s), F (s)
＝ P (s) ⁻¹・ R (s) (10)
As a result, although it is the same as Expression (4) in the first embodiment, the normative response characteristic R (s) used here is not the normative response characteristic R (s) ′ of the plant, and no filtering is performed. It is a normative response characteristic set for a thing.

In order to make the actual response of the operating angle / lift variable mechanism 112 follow a desired normative response, the normative response characteristic R (s) ′ of the plant needs to be a desired normative response characteristic R0 (s). For this reason, the normative response characteristic R (s) that does not include the filter processing may be calculated back as in the following equation.
R0 (s) = R (s) · F (s)
R (s) = R0 (s) · F ^-1 (s) ··· (11)
In this way, the phase difference between the normative response value and the response of the operating angle / lift variable mechanism 112 to the operation amount obtained by adding the feedforward operation amount and the feedback operation amount is prevented while preventing the operation amount from being excessive. Therefore, the actual response value can be satisfactorily followed by the reference response value.

Accordingly, when the target value changes due to the ramp response, as shown in FIGS. 7A and 7B, the control shaft rotation angle (actual response value) when the filtered value of the actual response value is fed back is shown. Fluctuations (see (C) in the figure) are also eliminated.
In addition, even when the step response changes, as shown in FIG. 8, when the control shaft rotation angle (actual response value) is small and the feedback control functions well, the occurrence of the undulation due to the phase difference is eliminated. The

  However, the manipulated variable (calculated value) exceeds the power supply voltage of the electric actuator 17 and the actual manipulated variable (driving voltage) is saturated (controlled by the energization duty ratio) such as when the target value changes greatly in the step response transition. When the duty ratio is maintained in the vicinity of 100%), the feedback control is not functioning, and when this saturation state is eliminated and the substantial feedback control is resumed, the feedback that has been subjected to the filter processing is performed. With the manipulated variable, there is a risk of delay in absorption of the deviation, generating undulations and lowering the convergence.

FIG. 9 shows a control block diagram of the third embodiment in which the problem when the operation amount is saturated as described above.
In the present embodiment, the filter processing in the feedback control is changed according to the conditions with respect to the second embodiment. For this reason, in the second embodiment, the filter processing is performed by one filter processing unit with respect to the operation amount obtained by adding the feedforward operation amount and the feedback operation amount. The first filter processing unit F is connected to the subsequent stage of the amount calculation unit C, and the second filter processing unit G is connected to the subsequent stage of the feedback manipulated variable calculation unit D, and the first filter processing unit F and the second filter processing unit G perform filter processing, respectively. The feedback operation amount and the feedback operation amount after being added are added and output to the variable operating angle / lift mechanism 112.

The first filter processing unit F has a certain filter processing function similar to the filter processing unit E of the first and second embodiments, but the second filter processing unit G is the same as the first filter processing unit F. The filter processing function is set to the maximum level, and the level can be gradually changed to level 0 in the filter processing stopped state.
The operation amount saturation state determination unit H determines whether or not the calculated value of the operation amount is a saturation state that is equal to or greater than the maximum driving force of the electric actuator 17.

Based on the determination result from the manipulated variable saturation state determination unit H, the filter level switching unit I switches the level of the filter function of the second filter processing unit G as follows.
When the calculated value of the manipulated variable is in a saturated state that is equal to or greater than the maximum driving force of the electric actuator 17, the filter processing of the second filter processing unit G is stopped (level = 0).
As a result, the feedback operation amount output from the second filter processing unit G is equal to the feedback operation amount calculated by the feedback operation amount calculation unit D preceding the second filter processing unit G.

The operation amount saturation state is determined by determining whether the calculated value (absolute value) of the operation amount (drive voltage V) is equal to or higher than the power supply voltage V0. Further, when the operation amount is controlled as the energization duty ratio, it can be determined depending on whether the energization duty ratio is near 100%.
When it is determined that the saturated state has been eliminated, the filter function level of the second filter processing unit G is gradually increased during the predetermined time t0 after the cancellation, and the same maximum level as that of the first filter processing unit F is obtained. Switch to.

The feedback manipulated variable F _FB output from the second filter processing unit G during this period is expressed by the following equation (12).
F _FB = [F _FB1 · (t0−t) + F _FB2 · t] / t0
F _FB1 : Feedback manipulated variable calculated by the feedback manipulated variable calculation unit F _FB2 : Calculated feedback manipulated variable value when F _FB1 is filtered at the maximum level by the second filter processing unit t: Elapsed time since the saturated state was canceled At times other than these, the second filter processing unit G performs the filtering process at the maximum level.

In this way, as in the first and second embodiments, the effects of preventing heat generation and preventing undulation fluctuations due to the phase difference can be obtained.
In addition, even when the manipulated variable is saturated, such as when the target value changes significantly, the saturation state is eliminated, and when the deviation between the normative response value and the actual response value is absorbed by feedback control, the deviation immediately after the saturation state is eliminated When is large, the deviation can be quickly reduced and the convergence can be improved by using the feedback operation amount set without performing the filtering process or by reducing the level of the filter function. Further, by increasing the filter function up to the maximum level after approaching the steady state over time, it is possible to suppress the amplitude of the manipulated variable from being excessive and to suppress heat generation and fuel consumption deterioration.

FIG. 10 shows a state change in the present embodiment. After the saturation state is eliminated, the filtering process is stopped and the level is gradually increased to shift from the operation amount A using the feedback operation amount F _FB1 to the operation amount B using the feedback operation amount F _FB2 .
When the present invention is applied to the center phase variable mechanism 113 that is the second variable valve mechanism, the control amount is changed only by the rotational phase of the intake valve drive shaft 3 and the operation amount is replaced by the operation amount of the electromagnetic retarder 24. It acts in the same manner as the control in the variable corner / lift mechanism 112, and the same effect is obtained.

In contrast to the control block diagrams of the first to third embodiments applied to the operating angle / lift variable mechanism 112, the control block diagram when the same embodiments are applied to the center phase variable mechanism 113 is shown in FIG. Since the mechanism 112 is simply changed to the center phase variable mechanism 113, the description is omitted.
If the present invention is applied to the operating angle / lift variable mechanism 112 and the center phase variable mechanism 113, it is desirable that the above effects are obtained in each mechanism, but a sufficient effect can be obtained even if only one of them is applied. Of course.

  In the above embodiment, the variable valve mechanism (variable operating angle / lift mechanism 112, variable center phase mechanism 113) that varies the characteristics of the intake valve is shown. However, the characteristics of the exhaust valve are variable. Also in the variable valve mechanism, the intake air amount characteristic can be made variable by making the exhaust valve characteristic variable, so that the same effect can be obtained by applying the present invention.

  Further, by improving the performance of the variable valve mechanism, an engine vibration suppressing effect can be obtained particularly during idling, and by applying to a variable valve mechanism for each bank of a V-type engine as in the embodiment, Performance between banks can be balanced, and effects such as avoiding a torque step and improving acceleration performance by avoiding the torque step can be obtained.

The block diagram of the internal combustion engine in embodiment of this invention. The perspective view which shows the structure of the working angle / lift variable mechanism in the said embodiment. The side view of the said working angle and lift variable mechanism. Sectional drawing which shows the center phase variable mechanism in the said embodiment. The control block diagram in 1st Embodiment of the said operating angle and lift variable mechanism. The control block diagram in 2nd Embodiment of the said operating angle and lift variable mechanism. The figure which shows an effect | action and effect when a target value changes with a lamp response in 2nd Embodiment. The figure which shows an effect | action and effect when a target value changes by step response in 2nd Embodiment. The control block diagram in 3rd Embodiment of the said operating angle and lift variable mechanism. The figure which shows the effect | action and effect of 3rd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 101 ... Internal combustion engine, 104 ... Electronically controlled throttle, 105 ... Intake valve, 107 ... Exhaust valve, 111a, 111b ... Oxygen sensor, 112a, 112b ... Operating angle / lift variable mechanism (VEL), 113a, 113b ... Center phase variable mechanism (VTC), 114 ... Electronic control unit (ECU)

Claims (9)

Equipped with a variable valve mechanism that changes the valve opening characteristics of the engine valve,
Target value calculating means for calculating a target value of the variable valve mechanism corresponding to a target value of the valve opening characteristic of the engine valve;
Normative response value calculating means for calculating a normative response value when the variable valve mechanism is caused to respond with a response characteristic defined with respect to the target value;
A feedforward manipulated variable calculating means for calculating a feedforward manipulated variable for causing the variable valve mechanism to respond with a response characteristic defined with respect to the target value;
Feedback manipulated variable calculating means for calculating a feedback manipulated variable for eliminating a deviation between the reference response value and the actual response value of the variable valve mechanism;
Based on the feedforward operation amount and the feedback operation amount, an operation amount calculation unit that calculates an operation amount output to the drive unit of the variable valve mechanism,
In a control device for a variable valve mechanism configured to include:
In order to remove the influence of the reaction force torque from the engine side, a filter means for smoothing the feedforward manipulated variable and the feedback manipulated variable using the same smoothing characteristic is provided.
A control apparatus for a variable valve mechanism, wherein the operation amount smoothed by the filter means is output to a drive means for the variable valve mechanism. Equipped with a variable valve mechanism that changes the valve opening characteristics of the engine valve,
Target value calculating means for calculating a target value of the variable valve mechanism corresponding to a target value of the valve opening characteristic of the engine valve;
Normative response value calculating means for calculating a normative response value when the variable valve mechanism is caused to respond with a response characteristic defined with respect to the target value;
A feedforward manipulated variable calculating means for calculating a feedforward manipulated variable for causing the variable valve mechanism to respond with a response characteristic defined with respect to the target value;
Feedback manipulated variable calculating means for calculating a feedback manipulated variable for eliminating a deviation between the reference response value and the actual response value of the variable valve mechanism;
Based on the feedforward operation amount and the feedback operation amount, an operation amount calculation unit that calculates an operation amount output to the drive unit of the variable valve mechanism,
In a control device for a variable valve mechanism configured to include:
In order to remove the influence of the reaction force torque from the engine side, a filter means for smoothing the feedforward manipulated variable and the feedback manipulated variable using the same smoothing characteristic is provided.
The operation amount smoothed by the filter means is output to the drive means of the variable valve mechanism,
The control apparatus for a variable valve mechanism, wherein the reference response value calculating means is configured to calculate a reference response value based on a prescribed response characteristic and a smoothing characteristic of the filter means. Equipped with a variable valve mechanism that changes the valve opening characteristics of the engine valve,
Target value calculating means for calculating a target value of the variable valve mechanism corresponding to a target value of the valve opening characteristic of the engine valve;
Normative response value calculating means for calculating a normative response value when the variable valve mechanism is caused to respond with a response characteristic defined with respect to the target value;
A feedforward manipulated variable calculating means for calculating a feedforward manipulated variable for causing the variable valve mechanism to respond with a response characteristic defined with respect to the target value;
Feedback manipulated variable calculating means for calculating a feedback manipulated variable for eliminating a deviation between the reference response value and the actual response value of the variable valve mechanism;
Based on the feedforward operation amount and the feedback operation amount, an operation amount calculation unit that calculates an operation amount output to the drive unit of the variable valve mechanism,
In a control device for a variable valve mechanism configured to include:
First filter means for smoothing the feedforward manipulated variable; second filter means for smoothing the feedback manipulated variable;
An operation amount output means for outputting an operation amount obtained by adding the feedforward operation amount via the first filter means and the feedback operation amount via the second filter means to the drive means of the variable valve mechanism;
Determining means for determining whether or not the calculated value of the operation amount is equal to or greater than a maximum driving force of the driving means;
Normal smoothing by the second filter means at other normal times is stopped from when it is determined that the manipulated variable is greater than or equal to the maximum drive amount until less than the maximum drive force and a predetermined time elapses. Or smoothing switching means for switching so as to weaken,
A control apparatus for a variable valve mechanism, comprising:   The variable valve mechanism according to claim 3, wherein the reference response value characteristic means calculates a reference response value based on the prescribed response characteristic and a smoothing characteristic by the first filter means. Control device.   When the calculated value of the manipulated variable is equal to or greater than the maximum driving force, the smoothing switching unit stops the smoothing of the second filter unit, and is less than the maximum driving amount until a predetermined time elapses. 5. The control device for a variable valve mechanism according to claim 3, wherein smoothing is gradually returned to a normal level.   6. The drive means according to claim 3, wherein the drive means is an electric actuator having an operation amount as a drive voltage, and it is determined that the drive amount is equal to or greater than the maximum drive amount by being equal to or greater than a drive power supply voltage. The control apparatus of the variable valve mechanism as described in any one.   The drive means is an electric actuator having an operation amount as an energization duty ratio, and determines that the operation amount is equal to or greater than the maximum drive amount based on an energization duty ratio in the vicinity of 100%. The control device for a variable valve mechanism according to claim 5.   The variable valve mechanism according to any one of claims 1 to 7, wherein the variable valve mechanism is a mechanism that varies at least one of an operating angle and a lift amount of an engine valve. Control device.   The variable valve mechanism control apparatus according to any one of claims 1 to 7, wherein the variable valve mechanism is a mechanism that varies a center phase of the engine valve.

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