JPH11270367A - Throttle control device of internal combustion engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve follow-up stability of opening of a throttle valve in an electronic throttle system using a torque motor. SOLUTION: An electronic throttle system using a torque motor 19 hardly absorb a non-linear characteristic of an electronic throttle by conventional PID(proportion, integration, differentiation) control as a motor torque characteristic is non-linear and is decided by a plural number of parameters (actual throttle opening, motor electric current) and throttle opening precision is lowered when there is no reduction gear train. Consequently, a controlled variable to make actual throttle opening TA coincide with a target throttle opening in accordance with a motor electric current required for generation of demand torque in consideration of kinetic energy based on estimation of existence of overshoot of the throttle valve 5 is computed. Accordingly the non-linear torque characteristic of the torque motor 19 etc., are absorbed and it becomes possible to carry out precise throttle control.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a throttle control device for an internal combustion engine that controls a degree of opening of a throttle valve by driving a torque motor according to an accelerator operation amount or the like.

[0002]

2. Description of the Related Art Conventionally, an internal combustion engine called an "electronic throttle system" for controlling a real throttle opening which is an actual throttle valve opening by driving a DC (direct current) motor as an actuator in accordance with an accelerator operation amount or the like. Is known. In such a throttle control device, for example, a motor current is supplied to a DC motor in accordance with a signal from an accelerator opening sensor that detects an accelerator opening corresponding to the amount of depression of an accelerator pedal.
When the C motor is driven, the throttle valve is opened and closed to control the amount of air supplied to the internal combustion engine. At this time, proportional / integral / differential control (Proportional Integral Differential Control; hereinafter) is performed on the DC motor so that the deviation between the signal from the throttle opening sensor that detects the actual throttle opening and the signal from the accelerator opening sensor is eliminated. , Simply referred to as “PID control”).

[0003]

It is known that the torque characteristics of a DC (direct current) motor can be approximated by T = KT × i. Here, T is a motor torque, KT is a torque constant, and i is a motor current. That is,
This shows that the motor torque T can be obtained almost linearly according to the motor current i.

On the other hand, in an electronic throttle system, the drive mechanism around the throttle valve is simplified, the number of parts is reduced, and the cost is reduced.
It is conceivable to use a torque motor instead of a DC motor as the actuator. The torque characteristic of this torque motor is such that the motor torque T [N · m] is a function T = f (θ, θ) of the actual throttle opening θ [°] and the motor current i [A].
i), that is, a two-dimensional map as shown in FIG. FIG. 14 shows only the relationship between the actual throttle opening θ and the motor torque T when the motor current i is on the positive side. Further, in a configuration in which the reduction gear train is not provided in a stage preceding the rotation axis of the throttle valve, the accuracy of the throttle opening is reduced.

Therefore, in an electronic throttle system using a torque motor, it is impossible to perform accurate throttle control by absorbing nonlinear torque characteristics and the like of the torque motor by feedback control of PID control.

Accordingly, the present invention has been made to solve such a problem, and it is possible to improve the follow-up stability of the opening degree of a throttle valve in an electronic throttle system using a torque motor, and to improve the drive mechanism around the throttle valve. It is an object to provide a throttle control device for an internal combustion engine that can be simplified.

[0007]

According to the throttle control device for an internal combustion engine of the present invention, the torque of the kinetic energy by the torque motor is reduced to zero according to the target throttle opening and the actual throttle opening. The required torque of the torque motor is calculated by the calculating means. A control amount for making the actual throttle opening controlled by the throttle control means coincide with the target throttle opening is calculated by the control quantity calculating means in accordance with the motor current based on the required torque and the actual throttle opening. In other words, in an electronic throttle system using a torque motor, the number of parts is small and the mechanism is simplified,
In particular, when the reduction gear train is eliminated, the actual throttle opening with respect to the target throttle opening tends to be affected by inertia, friction, and the like, and tends to overshoot. To cope with this, when calculating the required torque of the torque motor according to the target throttle opening and the actual throttle opening, the balance of the kinetic energy is made zero. As described above, the control amount is calculated in accordance with the motor current based on the required torque calculated in consideration of the kinetic energy of the torque motor in the throttle control system and the actual throttle opening. As a result, the non-linear torque characteristics of the torque motor are absorbed, so that accurate throttle control becomes possible, and the follow-up stability of the actual throttle opening with respect to the target throttle opening can be improved.

In the throttle control device for an internal combustion engine according to the second aspect, the total amount (integral value) of the acceleration energy and the brake energy applied to the throttle valve is canceled by the torque calculating means, so that the balance of the kinetic energy becomes zero. Is done. This allows the actual throttle opening to appropriately follow the transition state of the target throttle opening.

According to a third aspect of the present invention, the balance of the kinetic energy is zero based on the estimation of the presence or absence of the overshoot of the throttle valve by the torque calculation means, that is, the acceleration energy and the brake energy applied to the throttle valve are reduced. Are canceled out. As a result, it is possible to suppress the overshoot of the throttle valve when causing the actual throttle opening to follow the target throttle opening.

In the throttle control device for an internal combustion engine according to the present invention, when the actual throttle opening is made to follow the target throttle opening, the kinetic energy given when the torque calculation means is estimated to overshoot the throttle valve is the acceleration energy. Is switched to brake energy. This makes it possible to cause the actual throttle opening to follow the target throttle opening while suppressing overshoot of the throttle valve.

In the throttle control apparatus for an internal combustion engine according to the present invention, the presence or absence of overshoot of the throttle valve is determined by the actual throttle opening, the actual throttle speed which is a change amount of the actual throttle opening per unit time, and the target throttle opening. Can be appropriately estimated by calculating based on at least one of an elapsed time after the change of the time or a time corresponding to the target response time.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples.

FIG. 1 is a schematic configuration diagram showing an internal combustion engine to which a throttle control device for an internal combustion engine according to an embodiment of the present invention is applied, and peripheral devices thereof.

In FIG. 1, an internal combustion engine 1 is configured as a V-type six-cylinder four-cycle engine. Internal combustion engine 1
An air cleaner 3 is provided on the upstream side of the intake passage 2 of
An air flow meter 4 for detecting an intake air amount (intake air amount) is provided downstream of the air cleaner 3. A throttle valve 5 is provided downstream of the air flow meter 4 in the intake passage 2, and the opening degree of the throttle valve 5 is determined by the driving force of a torque motor 19 connected to a rotation shaft 5 a of the throttle valve 5. The throttle opening TA is controlled, and the amount of intake air supplied to the internal combustion engine 1 is adjusted. The actual throttle opening TA of the throttle valve 5 is detected by a throttle opening sensor 16. In addition,
Even during idling, the actual throttle opening TA is controlled by the driving force of the torque motor 19, whereby the intake air amount GN is controlled and feedback control is performed so that the engine speed NE matches the target idle speed. Further, the intake passage 2 is connected to each cylinder of the internal combustion engine 1 via an intake manifold 6, and intake air from the intake passage 2 is distributed and supplied to each cylinder via the inside of the intake manifold 6.

Intake manifold 6 is provided with an injector 7 corresponding to each cylinder, and fuel injected from each injector 7 is mixed with intake air and supplied to each cylinder. This air-fuel mixture is introduced into the combustion chamber 9 of each cylinder as the intake valve 8 opens and closes, is burned by the ignition of a spark plug 10, pushes down a piston 11, and applies torque to a crankshaft 12. The exhaust gas after combustion is discharged to the outside via an exhaust passage 14 with opening and closing of an exhaust valve 13. A crank angle sensor 15 is provided at a position close to the crankshaft 12, and a pulse signal is output from the crank angle sensor 15 at every 30 ° CA (Crank Angle).

Reference numeral 20 denotes an ECU (Electronic Control Unit:
The ECU 20 controls the driving of the injector 7 based on the intake air amount GN signal detected by the air flow meter 4 and the engine speed NE signal detected by the crank angle sensor 15, and controls the throttle opening sensor CPU that controls opening and closing of the throttle valve 5 based on the actual throttle opening TA signal detected by the accelerator pedal 16 and the accelerator opening Ap signal detected by the accelerator opening sensor 18 based on the amount of depression of the accelerator pedal 17.
The microcomputer mainly comprises a microcomputer 21, a ROM 22, a RAM 23, and the like.

Next, the configuration of the ECU 20 and its surroundings will be described in more detail with reference to FIG.

In the ECU 20, a CPU 21 reads an intake air amount GN signal, an engine speed NE signal, an actual throttle opening degree TA signal, an accelerator opening degree Ap signal, and the like, and requests each time according to the operating state of the internal combustion engine 1. This is a well-known central processing unit that calculates a fuel injection amount of the injector 7 and a target throttle opening TTP, which is a target command value of the throttle valve 5 by the torque motor 19, and the like.

The ROM 22 is a so-called program memory in which various control programs for controlling the operating state of the internal combustion engine 1, that is, a fuel injection control program, a throttle control program, and the like are stored in advance.
The CPU 21 executes various arithmetic processes in accordance with the program stored in the ROM 22. Also, RA
M23 is a so-called data memory that temporarily stores input / output data of various sensors, calculation processing data by the CPU 21, and the like.

The injector drive circuit 24 has an intake air amount GN
This is a circuit for driving the injector 7 by forming a signal of a predetermined pulse width corresponding to the fuel injection amount calculated through the CPU 21 based on the signal and the engine speed NE signal. As a result, an amount of fuel corresponding to the calculated fuel injection amount is injected and supplied from the injector 7 to each cylinder of the internal combustion engine 1. The A / D conversion circuit 27 converts the read intake air amount GN signal, actual throttle opening degree TA signal, accelerator opening degree Ap signal, cooling water temperature THW signal, and the like into an A / D signal.
This is a circuit for converting (analog-digital) and outputting the result to the CPU 21.

In the CPU 21, the target throttle opening TTP of the throttle valve 5 by the torque motor 19 and the throttle opening sensor 16
In response to the deviation from the actual throttle opening TA, the control duty (control amount) as a duty ratio signal subjected to PWM (pulse width modulation) conversion to reduce the deviation is calculated and output to the motor drive circuit 30. Is done. Then, the control current DU PWM-converted by the motor drive circuit 30
The torque motor 19 is driven by TY, and the actual throttle opening TA detected by the throttle opening sensor 16 is adjusted so as to finally coincide with the target throttle opening TTP.

Next, the configuration of the throttle control device for the internal combustion engine will be described with reference to FIGS.

2 and 3, the accelerator pedal 1
An accelerator opening sensor 18 is provided in 7, and the accelerator pedal 17 is connected to an accelerator lever 41. The accelerator lever 41 is connected to the accelerator return spring 4
The accelerator pedal 17 is urged in the return direction (clockwise direction) by the accelerator pedals 2a and 42b. Accelerator pedal 1
7 is not operated (accelerator OFF), the accelerator lever 41 is pressed by the accelerator return springs 42a, 4b.
2b, it is held in a state of contact with the accelerator fully closed stopper 43. While the internal combustion engine 1 is operating, the position of the accelerator lever 41 based on the operation amount of the accelerator pedal 17 is detected by the accelerator opening sensor 18 as the accelerator opening Ap.

On the other hand, a valve lever 44 is connected to the rotation shaft 5a of the throttle valve 5, and this valve lever 44
Is urged in the opening direction of the throttle valve 5 (upward in FIG. 2) by the retreat running spring 45. For this reason, the motor OFF (torque motor 19) shown in FIG.
When the power is turned off, the retreat running spring 45 holds the valve lever 44 at the intermediate stopper position where it contacts the intermediate lever 47. At this time, the intermediate lever 47
Is biased by the valve return spring 48 in the closing direction of the throttle valve 5 (downward in FIG. 2), and is in contact with the intermediate stopper 49.

That is, the pulling force of the valve return spring 48 is set to be larger than the pulling force of the retreat running spring 45. Therefore, when the motor is turned off as shown in FIG. 2B, the pulling force of the valve return spring 48 overcomes the pulling force of the retreat running spring 45, and the intermediate lever 47 comes into contact with the intermediate stopper 49 and is held. Is held at the intermediate stopper position (actual throttle opening TA = about 3 °) regulated by the intermediate stopper 49.

On the other hand, during the normal control (motor ON) shown in FIG. 2A, the torque motor 19 rotates forward or reverse according to the operation amount of the accelerator pedal 17, and the actual throttle opening TA of the throttle valve 5 Is adjusted, and the actual throttle opening TA of the throttle valve 5 at that time is detected by the throttle opening sensor 16. At this time, when increasing the actual throttle opening TA, the torque motor 19 is required.
When the motor motor on the positive side is supplied to the motor and the torque motor 19 is rotated forward, as shown in FIG.
4, the intermediate lever 47 is pushed up against the pulling force of the valve return spring 48, and the throttle valve 5 is driven in the opening direction. Conversely, when the actual throttle opening TA is reduced, a negative motor current is supplied to the torque motor 19 and the torque motor 19 is rotated in the reverse direction.
The valve lever 44 is lowered, and the throttle valve 5 is driven in the closing direction. When the throttle lever 5 is driven in the closing direction after the intermediate lever 47 is brought into contact with the intermediate stopper 49, the valve lever 44 is lowered against the pulling force of the retreating spring 45, and the throttle valve 5 is fully closed. When the valve lever 44 is closed to the stopper position (actual throttle opening degree TA = 0 °), the throttle fully closed stopper 4
6 to prevent further rotation.

Next, the structure of the torque motor 19 connected to the rotary shaft 5a of the throttle valve 5 used in the throttle control device for an internal combustion engine according to one embodiment of the present invention will be described with reference to FIGS. This will be described with reference to FIG. FIG. 5 is a diagram showing the torque motor 19 shown in FIG.
FIG. 3 is a view taken in the direction of arrow A with 3 removed.

As shown in FIG. 4, a throttle valve 5 is rotatably supported by bearings 61 and 62 on a throttle body 60 disposed in the middle of the intake passage 2. The throttle valve 5 is formed in a disk shape, and is fixed to the rotating shaft 5a with screws. By rotating the throttle valve 5 together with the rotation shaft 5a, the flow passage area of the intake flow passage 60a formed by the inner wall of the throttle body 60 is adjusted, and the amount of intake air passing through the intake passage 2 is controlled. You.

A valve lever 44 is press-fitted and fixed to one end of the rotary shaft 5a of the throttle valve 5, and is rotated together with the rotary shaft 5a. This valve lever 4
The fully closed position of the throttle valve 5 is defined by the contact of the throttle valve 4 with the throttle fully closed stopper 46. In addition,
By changing the screwing amount of the throttle fully closed stopper 46, the fully closed position of the throttle valve 5 is adjusted. In FIG. 4, the retreat running spring 45 and the like are omitted.

The throttle opening sensor 16 is disposed further on the end side of the rotary shaft 5a than the valve lever 44.
It comprises a contact portion 16a, a substrate 16b coated with a resistor, and a housing 16c. The contact portion 16a is press-fitted into the rotating shaft 5a, and is rotated together with the rotating shaft 5a. The board 16b is fixed to the housing 16c, and the contact portion 16a slides on the resistor applied to the board 16b. A constant voltage of 5 [V] is applied to the resistor applied to the substrate 16b. The sliding position between the resistor and the contact portion 16a is changed according to the opening of the throttle valve 5, and the output voltage value is changed. Is varied. The output voltage value from the throttle opening sensor 16 is input to the ECU 20, and the actual throttle opening TA of the throttle valve 5 is detected.

Further, as shown in FIGS. 4 and 5, the torque motor 19 is connected to the other end of the rotating shaft 5a by a rotor 65, a core 69, and a pair of solenoids 70 and 75. The end of the torque motor 19 is covered by a cover 63. The rotor 65 is composed of an iron core 66 and permanent magnets 67 and 68 press-fitted and fixed to the rotating shaft 5a, and is rotatably housed in a housing hole 69a formed by the inner wall of the core 69. The iron core 66 is formed in a cylindrical shape, and is press-fitted and fixed to the other end of the rotating shaft 5a. The permanent magnets 67 and 68 are formed in an arc shape, and
Are attached and fixed at equal intervals on the outer periphery of. Since the rotation range of the throttle valve 5 is usually 90 ° or less, the arc length of the permanent magnets 67 and 68 is long enough to allow a torque capable of rotating the rotor 65 within the rotation range of the throttle valve 5. Good. The permanent magnets 67 and 68 are neodymium-based.
A so-called samarium-cobalt system that generates high magnetic force,
Rare earth magnets are employed.

The core 69 is made of a thin plate made of a magnetic material.
The rotor 65 is rotatably housed in the housing hole 69a. The core 69 is formed in a slotless manner around the rotor 65 without any break. The solenoids 70 and 75 are formed by winding coils 72 and 77 around iron cores 71 and 76, respectively, and are press-fitted and fixed to a core 69. Coil 72, 7
7 is supplied with a control current from a pin 81 embedded in a connector 80. Also, the valve return spring 48
Has one end fixed to the iron core 66 and the other end fixed to the screw 64, and the valve return spring 48 urges the throttle valve 5 to the closed side.

Next, E used in the throttle control device for the internal combustion engine according to one embodiment of the embodiment of the present invention.
Referring to FIGS. 7, 8 and 9, based on the block diagram of FIG. 6 showing the processing procedure of the throttle control in the CPU 21 in the CU 20, FIG.

In FIG. 6, first, in a kinetic energy calculation process S1, based on a target throttle opening TTP set based on various sensor signals and an actual throttle opening TA from the throttle opening sensor 16, as described later. Thus, the kinetic energy TK is calculated. Further, in the friction torque calculation process S2, the bearings 61, 61 are determined according to the friction state at that time from the target throttle opening TTP and the actual throttle opening TA.
The friction torque of the throttle control system is calculated by 62 or the like. In the present embodiment, as shown in the map of FIG. 7, the friction torque [N · m] of the throttle control system by the bearings 61, 62 and the like is calculated according to the actual throttle speed ΔTA obtained by differentiating the actual throttle opening TA. You. Then, in the spring torque calculation processing S3, as shown in the map of FIG. 8, on the opening side where the actual throttle opening TA is larger than the intermediate stopper position, it corresponds to the valve return spring 48, and the actual throttle opening TA is the intermediate stopper. On the closed side smaller than the position, the spring torque [N · m] of the throttle control system corresponding to the evacuation travel spring 45 is calculated. Here, while the spring torque is calculated according to the actual throttle opening TA, in order to further improve the responsiveness, the target throttle opening TTP or the predicted throttle opening (= the actual throttle opening + the actual throttle speed) (Predetermined time) may be used to calculate the spring torque. Then, the kinetic energy TK, friction torque and spring torque calculated in the preceding stage are added to calculate the required torque TR [N · m] of the torque motor 19.

In the motor current calculation processing S4, as shown in the map of FIG. 9, the required torque TR [N.multidot.N] calculated in the preceding stage based on the actually measured value using the inverse model formula of TR = f (TA, IM). m] as a parameter, and the motor current IM [A] required to generate each required torque is determined by the actual throttle opening TA
It is calculated according to [°]. Here, the intermediate value in the map is calculated by an interpolation operation. FIG. 9A is a map for calculating the positive motor current IM [A] when the required torque TR [N · m] is on the positive side.
(B) is a map for calculating the negative motor current IM [A] when the required torque TR [N · m] is negative.
As described above, the motor current IM may have different characteristics due to the difference in the flow of the magnetic flux in the torque motor 19 between the positive side and the negative side.

Then, in the voltage conversion process S5, the converted voltage obtained by converting the motor current IM [A] calculated in the preceding stage by the resistance values of the motor coil resistance and the wiring (wire harness) resistance specific to the torque motor 19 is obtained. Is calculated.
Further, in the back electromotive voltage calculation processing S6, the back electromotive voltage is calculated according to the motor current IM [A] and the actual throttle opening TA [°] calculated in the preceding stage. Then, the required voltage VM [V] of the torque motor 19 is calculated by adding the converted voltage of the motor current IM calculated in the previous stage and the back electromotive voltage.
Next, in the required duty calculation processing S7, the required voltage VM [V] calculated in the preceding stage is multiplied by (100 / VB) and P is calculated.
A required DUTY of the torque motor 19 as a duty ratio signal converted by WM (pulse width modulation) is calculated. VB is the power supply voltage of the torque motor 19.

Further, in the error correction amount calculation processing S8, a correction amount for correcting an error between the model and the actual machine is calculated as described later. This correction amount is added to the request DUTY calculated in the previous stage, and is set as the control DUTY. This control D
When UTY is output to the motor drive circuit 30, the torque motor 19 is driven, and the actual throttle opening TA detected by the throttle opening sensor 16 is finally adjusted to match the target throttle opening TTP. .

Next, the balance of the kinetic energy TK (acceleration energy / brake energy) by the torque motor 19 used in the throttle control device for the internal combustion engine according to one embodiment of the present invention will be described with reference to FIG. This will be described with reference to a chart.

As shown in FIG. 10A, the actual throttle opening TA is changed with respect to the transition state of the target throttle opening TTP.
In order to stop the throttle valve 5 without overshooting, it is necessary to make the balance of the kinetic energy TK zero. That is, it is necessary to make the total acceleration energy, which is the integral value of the acceleration energy (acceleration torque), equal to the total brake energy, which is the integral value of the brake energy (brake torque). Here, the kinetic energy TK effectively acting on the throttle valve 5 is given by TK = J ×
{D (ΔTA) / dt}. J is the inertia of the throttle control system.

When the kinetic energy TK is applied as shown in FIG. 10 (b), the actual throttle speed ΔTA is changed as shown in FIG. 10 (c). Therefore, the target throttle opening TTP and the actual throttle opening TA
Is determined until the actual throttle opening TA coincides with the target throttle opening TTP, the required acceleration energy (acceleration torque) is determined.

The total acceleration energy, which is the integral value of the acceleration energy (acceleration torque), is represented by the following equation (1).

[0042]

## EQU1 ## ∫TK dt = J∫ ｛d (ΔTA) / dt｝ dt = ΔTA × J × (Δt / 2) (1) Here, the actual throttle at point A shown in FIG. The speed ΔTA is ΔTA = 2 × (Δθ / Δt). Therefore, ideally, the first half of the target response time Δt (Δt
/ 2), the acceleration energy (acceleration torque) is given, and the total acceleration energy, which is the integral value of the acceleration energy (acceleration torque), is reduced in the latter half (Δt / 2) by the total brake energy, the integral value of the brake energy (brake torque) By subtracting the energy, the throttle valve 5 is moved and stopped by the deviation Δθ between the target throttle opening TTP and the actual throttle opening TA at the target response time Δt.

Next, E used in the throttle control device for the internal combustion engine according to one embodiment of the embodiment of the present invention.
Kinetic energy calculation processing S in CPU 21 of CU 20
A description will be given based on a flowchart of FIG. 11 showing a specific processing procedure. This kinetic energy calculation routine is repeatedly executed by the CPU 21 in the ECU 20 at predetermined time intervals.

In FIG. 11, first, in step S101,
It is determined whether or not the target throttle opening TTP has changed. When the determination condition of step S101 is satisfied, that is, when there is a change in the target throttle opening TTP due to a change in the accelerator operation amount or the like, the process proceeds to step S102, and according to a deviation between the target throttle opening TTP and the actual throttle opening TA. A target throttle speed ΔTTP is calculated. on the other hand,
If the determination condition of step S101 is not satisfied, that is, if there is no change in the target throttle opening TTP, step S1 is executed.
02 is skipped.

Next, the routine proceeds to step S103, where the predicted throttle opening ETA is calculated by the following equation (2). Here, t is the elapsed time after the change of the target throttle opening TTP or a time half of the target response time Δt (Δt /
2).

[0046]

ETA = TA + ΔTA × t (2) Next, the process proceeds to step S104, and it is determined whether the target throttle opening TTP is equal to or larger than the predicted throttle opening ETA calculated in step S103. Step S10
4 is satisfied, that is, the target throttle opening TTP
Is greater than or equal to the predicted throttle opening ETA, the routine proceeds to step S105, where the kinetic energy is considered to be insufficient, and the acceleration torque TACC is calculated by the following equation (3).
Then, the calculated acceleration torque TACC is the kinetic energy T
K is determined, and this routine ends.

[0047]

TACC = (ΔTTP−ΔTA) × J (3) On the other hand, the determination condition of step S104 is not satisfied, ie,
Target throttle opening TTP is predicted throttle opening ETA
If it is smaller, the process proceeds to step S106, and it is determined that the kinetic energy has been exceeded, and the brake torque TBRA is calculated by the following equation (4). Here, K is a brake correction coefficient, which is a half of the target response time Δt (Δt /
Since it is sufficient to make the kinetic energy balance zero in 2),
Assuming that the operation cycle is ts, K = (2 / Δt) × ts. The kinetic energy TK is obtained by changing the sign of the calculated brake torque TBRA, and this routine is terminated.

[0048]

## EQU00004 ## TBRA = .DELTA.TA.times.J.times. (. DELTA.t / 2) .times.K (4) As described above, the kinetic energy TK is calculated while estimating the presence or absence of overshoot, and when it is estimated that overshoot does not occur. When the acceleration torque TACC is estimated to overshoot, the brake torque TBRA is applied, and the balance of the kinetic energy TK is made zero. In addition,
The determination condition in step S104 is changed so that the target throttle opening TTP is equal to or greater than the value obtained by multiplying the predicted throttle opening ETA by the coefficient α, and the coefficient α is adjusted so that the throttle valve 5 stops. You may make it.

Next, the E used in the throttle control device for an internal combustion engine according to one embodiment of the present invention will be described.
Kinetic energy calculation processing S in CPU 21 of CU 20
A description will be given based on a flowchart of FIG. 12 showing a modification of the first specific processing procedure. This kinetic energy calculation routine is repeatedly executed by the CPU 21 in the ECU 20 at predetermined time intervals.

In FIG. 12, first, at step S201
Then, the target throttle speed ΔTTP is calculated according to the deviation between the target throttle opening TTP and the actual throttle opening TA. Next, the process proceeds to step S202, and the predicted throttle opening ETA is similarly calculated by the above equation (2). Next, the routine proceeds to step S203, where the acceleration torque TACC is similarly calculated by the above equation (3). Next, the process proceeds to step S204, where the target throttle opening TTP is set to step S20.
It is determined whether the throttle opening is equal to or greater than the predicted throttle opening ETA calculated in step 2. The determination condition of step S204 is satisfied, that is, the target throttle opening TTP is equal to the predicted throttle opening E.
When it is larger than TA, the process proceeds to step S205,
It is determined that the acceleration torque TACC of the kinetic energy is still insufficient, and the brake torque TBRA is set to zero.

On the other hand, if the determination condition in step S204 is not satisfied, that is, if the target throttle opening TTP is smaller than the predicted throttle opening ETA, the flow shifts to step S206, and it is determined that the kinetic energy has exceeded the brake torque TBRA. It is similarly calculated by the above equation (4). Thereafter, the process proceeds to step S207, in which the kinetic energy TK is calculated by subtracting the brake torque TBRA calculated in step S205 or S206 from the acceleration torque TACC calculated in step S203, and this routine ends.

Next, E used in a throttle control device for an internal combustion engine according to one embodiment of the present invention will be described.
Error correction amount calculation processing S in CPU 21 in CU 20
8 will be described with reference to the flowchart of FIG. This error correction amount calculation routine is repeatedly executed by the CPU 21 in the ECU 20 at predetermined time intervals.

In FIG. 13, in step S301,
It is determined whether the target throttle opening TTP exceeds the actual throttle opening TA. When the determination condition of step S301 is satisfied, that is, when the target throttle opening TTP is larger than the actual throttle opening TA, the process proceeds to step S302, and the actual throttle opening TA is set to the target throttle opening T.
It is determined whether the vehicle is approaching the TP. Step S302
Is not satisfied, that is, when the deviation between the actual throttle opening TA and the target throttle opening TTP does not change without reducing or does not change or expands in reverse, step S3
The process proceeds to 03, where ΔIoffset as a predetermined current is added to the previous offset current Ioffset as an error correction amount, and the current value is set as the current offset current Ioffset, and this routine ends.

On the other hand, when the determination condition of step S301 is not satisfied, that is, when the target throttle opening TTP is equal to or less than the actual throttle opening TA, the process proceeds to step S304, and the target throttle opening TTP is reduced to the actual throttle opening TA.
Is determined. When the determination condition of step S304 is satisfied, that is, when the target throttle opening TTP is equal to the actual throttle opening TA, the process proceeds to step S305, and the previous offset current Ioffset as the error correction amount is used.
Is used as the current offset current Ioffset as it is, and this routine ends.

On the other hand, when the determination condition of step S304 is not satisfied, that is, when the target throttle opening TTP is less than the actual throttle opening TA, the process proceeds to step S306, and the actual throttle opening TA is changed to the target throttle opening TTP.
Is determined to be approaching. If the determination condition of step S306 is not satisfied, that is, if the deviation between the actual throttle opening TA and the target throttle opening TTP does not change without reducing or does not change, or conversely expands, step S307 occurs.
To the previous offset current I as an error correction amount.
ΔIoffset as a predetermined current is subtracted from the offset to make the current offset current Ioffset, and this routine ends. When the determination condition of step S302 or step S306 is satisfied, that is, when the deviation between the actual throttle opening TA and the target throttle opening TTP is reduced, the process proceeds to step S305, and as described above, the error correction amount is set as the error correction amount. The previous offset current Ioffset is used as it is as the current offset current Ioffset, and this routine ends.

As described above, the throttle control device for an internal combustion engine according to the present embodiment has the target throttle opening TT as the target of the throttle valve 5 set based on various sensor signals.
P and the required torque T of the torque motor 19 according to the actual throttle opening TA which is the actual opening of the throttle valve 5.
When calculating R, the torque calculating means achieved by the CPU 21 in the ECU 20 for setting the balance of the kinetic energy TK by the torque motor 19 to zero, the required torque TR calculated by the torque calculating means and the actual throttle opening TA And the actual throttle opening T according to the motor current IM calculated from
A in the ECU 20 for calculating a control duty as a control amount for making A equal to the target throttle opening TTP.
U21 and a control duty calculated by the control amount calculating means.
ECU 2 that drives the actual throttle opening TA by driving the ECU 9
0 and a throttle control means achieved by the motor drive circuit 30.

That is, in the electronic throttle system using the torque motor 19, the number of parts is small and the mechanism is simplified. In particular, since the reduction gear train is eliminated, the actual throttle opening TA with respect to the target throttle opening TTP becomes inertia. -It tends to be easily affected by friction and the like, and tends to overshoot. To cope with this, when calculating the required torque of the torque motor 19 according to the target throttle opening TTP and the actual throttle opening TA, the balance of the kinetic energy TK is made zero. As described above, the control DU is controlled in accordance with the motor current IM based on the required torque TR calculated in consideration of the kinetic energy TK of the torque motor 19 in the throttle control system and the actual throttle opening TA.
TY is calculated. As a result, the non-linear torque characteristic of the torque motor 19 is absorbed, so that accurate throttle control can be performed, and the follow-up stability of the actual throttle opening TA with respect to the target throttle opening TTP can be improved.

Further, in the throttle control device for an internal combustion engine according to the present embodiment, the torque calculation means achieved by the CPU 21 in the ECU 20 uses the acceleration torque TACC as acceleration energy.
Is made equal to the total brake energy, which is the integral value of the brake torque TBRA as the brake energy, to make the balance of the kinetic energy TK zero. That is, the total amount of the acceleration torque TACC and the brake torque TBRA given to the throttle valve 5 is canceled, and the balance of the kinetic energy TK is made zero. Thus, the actual throttle opening TA can appropriately follow the transition state of the target throttle opening TTP.

In the throttle control device for an internal combustion engine according to the present embodiment, the torque calculating means achieved by the CPU 21 in the ECU 20 reduces the balance of the kinetic energy TK to zero according to the estimation of the presence or absence of the overshoot of the throttle valve 5. It is assumed that. That is, the total amounts of the acceleration torque TACC and the brake torque TBRA given to the throttle valve 5 are canceled based on the estimation of the presence or absence of the overshoot of the throttle valve 5. As a result, the actual throttle opening TA
Overshoot of the throttle valve 5 at the time of following the target throttle opening TTP can be suppressed.

Further, in the throttle control apparatus for an internal combustion engine according to the present embodiment, when it is estimated that the throttle valve 5 overshoots by the torque calculation means achieved by the CPU 21 in the ECU 20, the kinetic energy TK is used as acceleration energy. This is to switch from the acceleration torque TACC to the brake torque TBRA as the brake energy. That is, the actual throttle opening TA is changed to the target throttle opening TT.
When the throttle valve 5 is assumed to overshoot, the kinetic energy T given when the throttle valve 5 is estimated to overshoot.
K is switched from the acceleration torque TACC to the brake torque TBRA. Thus, the actual throttle opening TA can be made to follow the target throttle opening TTP while suppressing overshoot of the throttle valve 5.

Further, in the throttle control device for an internal combustion engine of the present embodiment, the presence or absence of overshoot of the throttle valve 5 is the actual throttle opening TA and the actual throttle speed ΔTA which is a change amount per unit time of the actual throttle opening TA. At least one of the elapsed time t after the change in the target throttle opening TTP or the time corresponding to the target response time Δt.
It is estimated by one. That is, the actual throttle opening TA, the actual throttle speed ΔTA which is the amount of change per unit time of the actual throttle opening TA, the elapsed time t after the target throttle opening TTP changes, or the time corresponding to the target response time Δt. , The presence or absence of the overshoot of the throttle valve 5 can be appropriately estimated.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an internal combustion engine to which an internal combustion engine throttle control device according to an embodiment of the present invention is applied and peripheral devices thereof.

FIG. 2 is a schematic diagram showing a main configuration of a throttle control device for an internal combustion engine according to an example of an embodiment of the present invention.

FIG. 3 is a perspective view showing a main configuration of a throttle control device for an internal combustion engine according to an example of the embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a configuration of a torque motor connected to a rotary shaft of a throttle valve used in a throttle control device for an internal combustion engine according to one embodiment of the present invention. .

FIG. 5 is an arrow view of the torque motor of FIG. 4 with the cover removed and viewed from the direction A.

FIG. 6 is an EC used in a throttle control device for an internal combustion engine according to an embodiment of the present invention.
FIG. 9 is a block diagram showing a processing procedure of throttle control in a CPU in U.

FIG. 7 is a map for calculating a friction torque from an actual throttle speed in the friction torque calculation processing of FIG. 6;

FIG. 8 is a map for calculating a spring torque from an actual throttle opening in the spring torque calculation processing of FIG. 6;

FIG. 9 is a map for calculating a motor current from an actual throttle opening and a required torque in the motor current calculation processing of FIG. 6;

FIG. 10 is a time chart illustrating a balance of kinetic energy by a torque motor used in a throttle control device of an internal combustion engine according to one example of an embodiment of the present invention.

FIG. 11 is a flowchart showing a specific processing procedure of the kinetic energy calculation processing of FIG.

FIG. 12 is a flowchart illustrating a modified example of the specific processing procedure of the kinetic energy calculation processing of FIG. 6;

FIG. 13 is a flowchart illustrating a specific processing procedure of the error correction amount calculation processing of FIG. 6;

FIG. 14 is a characteristic diagram showing a relationship between an actual throttle opening and a motor torque when a throttle valve is driven using a torque motor in a conventional throttle control device, using a motor current as a parameter.

[Explanation of symbols]

 Reference Signs List 1 internal combustion engine 5 throttle valve 16 throttle opening sensor 18 accelerator opening sensor 19 torque motor 20 ECU (electronic control unit)

Claims (5)

[Claims] 1. A required torque of a torque motor is calculated in accordance with a target throttle opening of a throttle valve set based on various sensor signals and an actual throttle opening which is an actual opening of the throttle valve. A torque calculating means for setting a balance of kinetic energy by the torque motor to zero; and the actual throttle according to a motor current calculated from the required torque calculated by the torque calculating means and the actual throttle opening. Control amount calculating means for calculating a control amount for making the opening equal to the target throttle opening degree; and the torque motor is driven by the control amount calculated by the control amount calculating means, and the actual throttle opening degree is calculated. And a throttle control means for controlling the throttle control of the internal combustion engine. 2. The method according to claim 1, wherein said torque calculating means sets the kinetic energy balance to zero by making a total acceleration energy, which is an integral value of acceleration energy, equal to a total brake energy, which is an integral value of brake energy. Claim 1
3. The throttle control device for an internal combustion engine according to claim 1. 3. The internal combustion engine according to claim 1, wherein the torque calculation unit sets the balance of the kinetic energy to zero according to the estimation of the presence or absence of overshoot of the throttle valve. Throttle control device. 4. The throttle control of an internal combustion engine according to claim 3, wherein said torque calculation means switches said kinetic energy from acceleration energy to brake energy when it is estimated that said throttle valve overshoots. apparatus. 5. The method according to claim 5, wherein the presence or absence of an overshoot of the throttle valve is determined by determining the actual throttle opening, an actual throttle speed which is a variation per unit time of the actual throttle opening,
The throttle control of an internal combustion engine according to claim 3 or 4, wherein the throttle control is estimated based on at least one of an elapsed time after the change of the target throttle opening and a time corresponding to the target response time. apparatus.